(a) Given that the path length of the cuvette is 1 cm, what is the extinction coefficient of the 0.020 mM Yellow 5 dye at lambda max?(b) Given the data in the table below, what is the concentration of the diluted solution?Stock solution concentration 0.075 MStock solution absorbance 1.84Diluted solution absorbance 0.78

Answers

Answer 1

Answer:

(a). Kindly check the explanation section.

(b). 24.5 M^-1 cm^-

(c). 0.0318 M

Explanation:

So, we are given the following data parameters which is going to aid us in solving the above Question;

The path length = 1cm, extinction coefficient = unknown, absorbance is unknown and concentration= 0.02mM.

Using the formula below; we can determine the extinction coefficient as;

Absorbance = extinction coefficient × concentration × path length. -----------(1).

(a). Since, the absorbance is not given in the Question it won't be possible to determine the value of the extinction coefficient. Thus, say the value of absorbance = A.

Then, extinction coefficient = A/ 0.02 × 1 cm.

(b). Making use of the formula above, the extinction coefficient can be Determine as follows;

extinction coefficient = 1.84/0.075 × 1 = 24.5 M^-1 cm^-1.

(c). The concentration can be Determine by also making use of the formula above and making the concentration the subject of the formula;

Concentration = absorbance/ extinction coefficient × path length.

Concentration = 0.78/24.5 M^-1 cm^-1. × 1cm = 0.0318 M.


Related Questions

The first excited electronic energy level of the helium atom is 3.13 x 10-18 J above the ground level. Estimate the temperature at which the electronic motion will begin to make a significant contribution to the heat capacity. That is, at what temperature will the ratio of the population of the first excited state to the ground state be 5.0%?

Answers

Answer:

75603.86473 K

Explanation:

Given that:

The 1st excited electronic energy level of He atom = 3.13 × 10⁻¹⁸  J

The objective of this question is to estimate the temperature at which the ratio of the population will be 5.0 between the first excited state to the ground state.

The formula for estimating the ratio of population in 1st excited state to the ground state can be computed as:

[tex]\dfrac{N_2}{N_1} = e ^{^{-\dfrac{(E_2-E_1)}{KT}}} = e ^{^{-\dfrac{(\Delta E)}{KT}}}[/tex]

From the above equation:

Δ E = energy difference =  3.13 × 10⁻¹⁸  J

k = Boltzmann constant = 1.38 × 10⁻²³  J/K

[tex]\dfrac{N_2}{N_1} = 0.5[/tex]

Thus:

[tex]0.05 =e^{^{ -\dfrac{3.13 \times 10^{-18} \ J}{1.38\times 10^{-23 \ J/K}\times T}}}[/tex]

[tex]In (0.05) = { -\dfrac{3.13 \times 10^{-18} \ J}{1.38\times 10^{-23 \ J/K}\times T}}}[/tex]

[tex]-3.00 = { -\dfrac{3.13 \times 10^{-18} \ J}{1.38\times 10^{-23 \ J/K}\times T}}}[/tex]

[tex]-3.00 = -226811.5942 \times \dfrac{1}{T}[/tex]

[tex]T = \dfrac{-226811.5942}{-3.00 }[/tex]

T = 75603.86473 K

Describe the role of chloroplasts in photosynthesis. (ASAP)

Answers

Answer:

Chloroplasts absorb sunlight and use it in conjunction with water and carbon dioxide gas to produce food for the plant. Chloroplasts capture light energy from the sun to produce the free energy stored in ATP and NADPH through a process called photosynthesis.

Explanation:

Sunlight is consumed by chloroplasts and used in combination with water and carbon dioxide gas to make food for the plant. In order to produce the free energy contained in ATP and NADPH via a process called photosynthesis, chloroplasts absorb light energy from the sun.

Which two types of energy are formed by the transformation shown in the
photo?
A. Chemical energy
thermal energy
B. Thermal energy -
electrical energy
C. Thermal energy -
chemical energy
D. Chemical energy
-
electromagnetic energy
PREVIOUS

Answers

Explanation:

i cant even see any thing

Answer: A and D

Explanation:

PLZ HELP ASAP

Which would increase the reaction rate?

Check all that apply.

A. Stirring the reaction
B. Raising the activation energy
O C. Adding a catalyst
D. Raising the temperature

Answers

Answer:

adding a catalyst will increase the reaction rate.

Explanation:

im like 95% sure thats right.

Answer:

A. C. D

Explanation:

ap ex

Which element is most likely suspected?
iron
Sulfur
Chromium
Nickel

Answers

Answer: sulfur

Explanation:

Answer:

its sulfur babes

Explanation:


A student writes Ba?- as the symbol for a barium ion. Explain what is incorrect about the symbol.

Answers

Answer:

ion is missing

Explanation:

4 As a boulder rolls from the top of a hill to the bottom, how do its potential and kinetic energy change? *

A Potential and kinetic energy both increase.

B Potential increases and kinetic decreases.

C Potential decreases and kinetic increases.

D Potential and kinetic energy both decrease..

Answers

Answer:

c. Potential decreases and kinetic increases.

Explanation:

As the boulder is rolling down the hill, potential energy decreases as kinetic energy increases.

Please Brainliest me

Answer

C. Potential decreases and kinetic increases

In ionic bonding, atoms__.
A. share electrons
B. are connected by strong electrical forces
C. lose protons and form ions
D. stop moving completely

Answers

In ionic bonding, atoms SHARE ELECTRONS

An atom of an element contains 20 protons, 20 neutrons, and 20 electrons. This element is in Group *

Answers

Answer:

it is calcium. it is in group(llA).

Answer:

calcium it lies in group(IIA)

hope it is helpful to you

Hugh wrote the properties of physical and chemical weathering in the table shown.
Types of Weathering
Physical Weathering
Chemical Weathering
Temperature may break the rocks Can be caused by chemicals in water
Can be caused by snow and pressure Composition of rock remains same
Why is Hugh's table incorrect? (5 points)
a
Chemicals in water cause physical weathering.
b
ос
Temperature is unable to break rocks physically.
Chemical weathering changes the composition of rocks.
Physical weathering is unaffected by snow and pressure.
Od

Answers

Answer:

I am sure that the C one is correct

Answer:

how is this college level..im doing this in middle school..

Explanation:

what step of the scientific method do we decide whether our hypothesis was correct or not

Answers

Test Your Hypothesis by Doing an Experiment
Your experiment tests whether your prediction is accurate and thus your hypothesis is supported or not. It is important for your experiment to be a fair test.

A ball was massed in a dish. The total mass was 15.6 grams. Treball was placed in a
cylinder containing 26.7 ml of water. The new water level was 38.9 ml. If the mass of the dish is 1.03 grams, what is the mass of the ball?

Answers

Answer:

14.57g

Explanation:

Given parameters:

Mass of dish + ball  = 15.6g

Initial volume of water in the cylinder  = 26.7mL  

Final volume of water in the cylinder  = 38.9mL

Mass of dish = ?

Unknown

Mass of the ball = ?

Solution;

 Since the mass of ball and dish is 15.6g,

 Mass of the ball  =Mass of ball + dish  - mass of the dish

 Insert the parameters and solve;

 Mass of the ball  = 15.6g  - 1.03g  = 14.57g

Nitrogen gas at 300 k and 200 kpa is throttled adiabatically to a pressure of 100 kpa if the change in kinetic energy is negligble the temperature of the nitrogen after throttling will be:_________

Answers

Answer:

The temperature of the Nitrogen after throttling is  [tex]T_2 = 300 \ K[/tex]

Explanation:

From the question we are told that

   The  temperature is  [tex]T_1 = 300 \ K[/tex]

    The pressure is  [tex]P = 200 \ kPa = 200 * 10^{3} \ Pa[/tex]

    The pressure after being  [tex]P_1 = 100 \ kPa = 100 * 10^{3} \ Pa[/tex]

   

Generally from the first law of thermodynamics we have that

      [tex]Q - W = \Delta U + \Delta K[/tex]

Here [tex]\Delta U[/tex]  is the change internal  energy which is mathematically represented as

            [tex]\Delta U = C_p (T_2 - T_1)[/tex]

Here      [tex]C_p[/tex] is the specific heat of the gas at constant pressure

        [tex]\Delta K[/tex]  is the change kinetic energy which is negligible

         Q  is the thermal  energy  which is Zero for an adiabatic process

         W  is the work done and the value is zero given that the gas was throttled adiabatically

So

      [tex]0= \Delta U +0[/tex]

=>   [tex]\Delta U = 0[/tex]

=>  [tex](T_2 - 300) = 0[/tex]

=>   [tex]T_2 = 300 \ K[/tex]

     

Explain some of the uses of metals based on their properties.

Answers

Answer:

Explain some of the uses of metals based on their properties.

Explanation:

Metals have a shiny or metallic luster and are good conductors of heat and electricity, they can be bent and pounded in various shapes, so they can be used on cars, coins, some pipes, keys, and and a flag.

What is the name of the region (on the graph) where the temperature remains constant while heat is being absorbed (or released)?

Answers

Answer:

A heating curve graphically represents the phase transitions that a substance undergoes as heat is added to it. The plateaus on the curve mark the phase changes. The temperature remains constant during these phase transitions.

How many moles are in a balloon that is 50.2L, 755 mmHg and -22.0C?

Answers

Answer:

n ≈ 2.42 moles

General Formulas and Concepts:

Chem

Ideal Gas Law: PV = nRT

P is pressure in mmHgV is volume in litersn is number of molesR is a constant (62.4 L · mmHg/mol · k)T is temperature in Kelvins

K = °C + 273

Explanation:

Step 1: Define

V = 50.2 L

P = 755 mmHg

T = -22.0°C = 251 K

Step 2: Find moles n

(755 mmHg)(50.2 L) = n(62.4 L · mmHg/mol · k)(251 K)

37901 mmHg · L = n(15662.4 L · mmHg/mol)

n = 2.41987 moles

Step 3: Check

We are given 3 sig figs. Follow sig fig rules.

2.41987 moles ≈ 2.42 moles

1. What is the molar mass of Al?

Answers

Answer:

26.981539 u

Explanation:

How is active immunity different from passive immunity? Give examples of both active and passive natural and artificial immunity.

Answers


There are two types of adaptive immunity: active and passive. Active Immunity - antibodies that develop in a person's own immune system after the body is exposed to an antigen through a disease or when you get an immunization (i.e. a flu shot). This type of immunity lasts for a long time.
sorry if this didn't help!!

Which of the following is the best definition of a chemical change?
A. A change in a substance where no new substance forms
B. A change in a substance where energy is conserved
C. A change in a substance where a phase change occurs
D. A change in a substance where one or more new substances form

Answers

Answer:it's D

Explanation:

A chemical change, unlike a physical change, is the formation of new products or one or more new substances formed from the reactants. Thus, option D is correct.

What is a chemical change?

A chemical change is a type of change where the reactants break or combine to form a new product that is different from the reactants. Unlike physical change, they are not reversible and can be seen in combustion, neutralization, decomposition, redox reactions, etc.

It is a change in a matter where the reactant undergoes breaking or forming of the bonds to yield a new product. It is accompanied by changes in temperature, color, precipitation, and odor.

Therefore, a chemical change results in the formation of a new substance.

Learn more about chemical change here:

https://brainly.com/question/18690541

#SPJ5

In a vacuum, if a 0.045 kg golf ball is accelerated upward at 2.5 m/s2 by a hair dryer, how much force is required to accelerate the ball?

Answers

Answer:

F = 0.553 N

Explanation:

Given that,

Mass of a golf ball, m = 0.045 kg

Acceleration in upward direction, a = 2.5 m/s²

We need to find the force is required to accelerate the ball. Let the force be F. Using the second law of motion as follows :

F = m(a+g)

So,

F = 0.045 (2.5+9.8)

F = 0.553 N

So, the force required to accelerate the ball is 0.553 N.

A student is using colored beads to model 1 molecule of LaTeX: Ca_3\left(PO_4\right)_2C a 3 ( P O 4 ) 2. The student uses blue beads to model Calcium, red beads to model Phosporus, and green beads to model Oxygen. How many of each color will the student need to make their model?

Answers

Answer:

3 blue beads

1 red beads

4 green beads

Explanation:

The compound given:

               Ca₃PO₄

Elements in the compound are:

Ca

P

O

  Number of atoms are :

Ca - 3

P - 1

O  - 4

blue beads to model Calcium

red beads to model Phosphorus

green beads to model Oxygen

    3 blue beads

    1 red beads

   4 green beads

Las Vegas, Nevada is in a desert. How does its rapid population growth affect the
water supply? Name at least two specific ways that human activities affect the quality
of groundwater

Answers

Answer:

Many areas of the United States experience explosive population growth. The more people that reside someplace, the more demand there is for water there. Often these urban-growth expansions are unplanned and place extraordinary stress on the water supply system, mainly on the groundwater. The stress often depletes groundwater supply, thereby causing wells to dry up. Then water must be brought from somewhere else to support the local population.

Such situations have occurred all over the United States. For example, increased population growth in the southwestern United States has significantly lowered the water table 50 to 200 feet (depending on the area) since the 1940s. Managing urban growth, efforts to reduce water demand, conservation of the resource, and attempts to increase the water supply all address the problem of exceeding water resource limits.

Human activities affect groundwater quality.

Here are some sources and possible solutions to groundwater pollution:

Agriculture—Reduce usage of pesticides and fertilizers.

Landfills—Monitor for leakage and repair linings.

Underground storage tanks—Remove damaged and unused tanks.

Household wastes—Properly dispose of household hazardous waste.

Septic tank leaks—Properly maintain and repair tanks.

Explanation:

This came from the K12 learning course read this and the answer will be there. I underlined the important parts for the answer.

The energy of a pendulum is recorded at different positions in the table below. Use the data in the table to determine the amount of kinetic energy the pendulum had at Position 2. Record your answer below.

Please help me I just want to get this test over with

Answers

Answer:

so i got 34.5

Explanation:

Most of the mass in an atom is found in the...?

Answers

Most of the mass in an atom is found in the nucleus

Plate Tectonics Lab Report

Instructions: In the Plate Tectonic lab you will investigate the interactions between continental and oceanic plates at convergent, divergent, and transform boundaries around the globe. Record your observations in the lab report below. You will submit your completed report.


Name and Title:

Include your name, instructor's name, date, and name of lab.

Kaleb, Ms. Young, 11/25/2020, Plate Tectonics Lab Report

Objective(s):

In your own words, what was the purpose of this lab?

To look at interactions between continental and oceanic plates.

Hypothesis:

In this section, please include the if/then statements you developed during your lab activity for each location on the map. These statements reflect your predicted outcomes for the experiment.

Location One: Select three events that you predict will be observed. If I explore two continental plates at a convergent boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Two: Select three events that you predict will be observed. If I explore two continental plates at a divergent boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Three: Select three events that you predict will be observed. If I explore two continental plates at a transform boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Four: Select two events that you predict will be observed. If I explore two oceanic plates at a convergent boundary, then I will observe:
earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Five: Select three events that you predict will be observed. If I explore two oceanic plates at a divergent boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Six: Select two events that you predict will be observed. If I explore two oceanic plates at a transform boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading



Procedure:

The procedures are listed in your virtual lab. You do not need to repeat them here. Please be sure to identify the test variable (independent variable), outcome variable (dependent variable).

Reminder: Test variable = the item you are changing or manipulating; Outcome variable = the item you are measuring

Test variable (independent variable):

Outcome variable (dependent variable):

Data:

Record the data from each location below.

Location Name

Boundary Type
(C=Convergent, D=Divergent, or T=Transform)

Year Observed
(5, 10, or 20 million years)

Geologic Events Observed
(earthquakes, faults, ocean formation, mountains, volcanoes, island chains, seafloor spreading)

Location One
Himalayas



5

Event 1-

20

Event 2-

Location Two
East Africa



5

Event 1-

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Five: Select three events that you predict will be observed. If I explore two oceanic plates at a divergent boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Six: Select two events that you predict will be observed. If I explore two oceanic plates at a transform boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading



Procedure:

The procedures are listed in your virtual lab. You do not need to repeat them here. Please be sure to identify the test variable (independent variable), outcome variable (dependent variable).

Reminder: Test variable = the item you are changing or manipulating; Outcome variable = the item you are measuring

Test variable (independent variable):

Outcome variable (dependent variable):

Data:

Record the data from each location below.

Location Name

Boundary Type
(C=Convergent, D=Divergent, or T=Transform)

Year Observed
(5, 10, or 20 million years)

Geologic Events Observed
(earthquakes, faults, ocean formation, mountains, volcanoes, island chains, seafloor spreading)

Location One
Himalayas



5

Event 1-

20

Event 2-

Location Two
East Africa



5

Event 1-

Please answer quickly!!!
I will award 50 points!

Answers

Answer:

In this section, please include the if/then statements you developed during your lab activity for each location on the map. These statements reflect your predicted outcomes for the experiment.

Location One: Select two events that you predict will be observed. If I explore two continental plates at a convergent boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Two: Select three events that you predict will be observed. If I explore two continental plates at a divergent boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

Location Three: Select three events that you predict will be observed. If I explore two continental plates at a transform boundary, then I will observe:

earthquakes

faults

ocean formation

mountains

volcanoes

island chains

seafloor spreading

This is all I have for now! Hope this can help! :)

1. The state of Georgia has seen their water table become lower. What does this mean?
The amount of groundwater is increasing.
Their groundwater is being recharged by rain.
The amount of groundwater is decreasing.
Their groundwater is flowing to confined aquifers.

Answers

Answer:

The amount of groundwater is decreasing.

Explanation:

In an ecosystem like the state of Georgia where the water table has become lower it means that the amount of groundwater in the ecosystem is decreasing.

What is an ecosystem?

Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.

Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.

Learn more about ecosystem,here:

https://brainly.com/question/19267717

#SPJ5

What is the most abundant element on Earth?
A oxygen
B Cobalt
C Carbon
D Iron
5
Any substance represented by a chemical formula
A Homogenous mixture
B Heterogenous Mixture
C elements
D pure substance

Answers

Answer:

oxygen is the most abundant element on the earth.

Calculate the pH during the titration of 20.00 mL of 0.1000 M trimethylamine, (CH3)3N(aq), with 0.2000 M HClO4(aq) after 9.48 mL of the acid have been added.

Answers

Complete Question

Calculate the pH during the titration of 20.00 mL of 0.1000 M trimethylamine, (CH3)3N(aq), with 0.2000 M HClO4(aq) after 9.48 mL of the acid have been added.Kb of trimethylamine = 6.5 x 10-5.

Answer:

The pH is  [tex]pH = 9.84[/tex]  

Explanation:

From  the question we are told that

   The  volume of trimethylamine, (CH3)3N(aq) is [tex]V_{t} = 20.00mL[/tex]

    The concentration of trimethylamine is [tex]C_t = 0.1000 \ M[/tex]  

    The  volume of HClO4(aq) is [tex]V_{h} = 9.48 mL[/tex]

    The  concentration of  HClO4(aq) is  [tex]C_h = 0.200 M[/tex]

      The Kb  value is  [tex]K_b = 6.5 * 10^{-5}[/tex]

Generally the the pOH of this reaction is mathematically represented as

       [tex]pOH = pK_b + log [\frac{N_h}{N_b} ][/tex]

Here [tex]N_h[/tex] is the number of moles of acid which is evaluated as

      [tex]N_h = C_h * V_h[/tex]

=>    [tex]N_h = 0.200 * 9.48[/tex]

=>    [tex]N_h = 1.896[/tex]

Here [tex]N_t[/tex] is the number of moles of acid which is evaluated as

      [tex]N_t = C_t * V_t[/tex]

=>    [tex]N_t = 0.100 * 20[/tex]

=>    [tex]N_t = 2[/tex]

So

     [tex]pOH = -log(K_b) + log [\frac{N_h}{N_b} ][/tex]

     [tex]pOH = -log(6.5*10^{-5}) + log [\frac{1.896}{2} ][/tex]

=>   [tex]pOH = 4.1639[/tex]

Generally the pH is mathematically represented as

       [tex]pH = 14 - pOH[/tex]

=>    [tex]pH = 14 - 4.1639[/tex]  

=>    [tex]pH = 9.84[/tex]  

       

What shape is the s sublevel? *
sphere
freaky
peanut
daisy

Answers

Answer:

Sphere

Explanation:

The shape of the s-sublevel is spherical in shape.

This sublevel has an azimuthal quantum number of 0 and it is spherical in shape;

p - sublevel has a dumb-bell shape d - sublevel has double dumb - bell shape f - sublevel has a complex shape

Describe the process of photosynthesis (including what components get released). ASAP

Answers

Answer: It is convenient to divide the photosynthetic process in plants into four stages, each occurring in a defined area of the chloroplast: (1) absorption of light, (2) electron transport leading to the reduction of NADP+ to NADPH, (3) generation of ATP, and (4) conversion of CO2 into carbohydrates (carbon fixation). All four stages of photosynthesis are tightly coupled and controlled so as to produce the amount of carbohydrate required by the plant. All the reactions in stages 1 – 3 are catalyzed by proteins in the thylakoid membrane. The enzymes that incorporate CO2 into chemical intermediates and then convert it to starch are soluble constituents of the chloroplast stroma (see Figure 16-34). The enzymes that form sucrose from three-carbon intermediates are in the cytosol.

Answer:

Glucose gets made using Carbon dioxide, water, and sunlight. Glucose serves as food for the plant. This was the answer to your question

Explanation:

Other Questions
Why does Hitler dislike (hate/fear) the philosophy of Marxism? (At least 2 sentences)Pls pls plssss answerrr!! In the previous problem, suppose the project requires an initial investment in net working capital of $150,000, and the fixed asset will have a market value of $185,000 at the end of the project. What is the projects Year 0 net cash flow? Commonalities used to group languages together include __________. A. origins, sounds, and words B. sounds, dialects, and accents C. letters, vowels, and body language D. signing, spoken, and written similarities how have black woman specifically suffered from racial and sexism discrimination? Why do you think John Locke favored the Republic form of government? One reason for imbalance or disequilibrium in the family during the adolescent years is that parentsA. are too involved in their own careers to notice their children.B. may be experiencing their own type of "identity crisis."C. may be pushing their child toward financial independence too early.D. are too restrictive of their adolescents' finances. A synonym for mastery might be:instinctinvolvementexpertisebossiness Why is it important to lean forward and listen please answer the question in the picture 40 points I need some help and fastSolve this plz check wether all the answers are correct or not. please? Several kilometers from a volcano a geologist observes an old lava flow made up of a dark -colored basalt rock.The geologist infer that the lava must have had A spring-loaded toy gun is used to shoot a ball straight up inthe air. The ball reaches a maximum height H, measuredfrom the equilibrium position of the spring. The same ball is shot straight up a second time from the same gun, but this time the spring is compressed only half as far before firing. How far up does the ball go this time? whats the nth term of -5,-4,-1,4,11,20,31 Select the correct answer.Bella is moving the camera physically to the left to capture a fast-paced shot. Which technique is she using?OApan leftOB.truck leftO c.truck rightOD.zoom leftOE.pan right What is the solution of the proportion x1/2 = x4/5 ? What is the solution to x^6 6x ^5 + 15x ^4 20x ^3 + 15x^ 2 6x + 1 0? x = 0 x = 1 all real numbers all real numbers except zero Here is my questionWhich statement can be used to classify this triangle as an isosceles triangle?Angle F is a right angle.Sides DE and EF are congruent.Sides FD and DE are congruent.Sides EF and FD are congruent. Which of the following statements is best demonstrated by the model? Write a 4-5 sentence summary about thomas jeffersons presidency. Please help!