3.The cost of renting a car is $46 /wk plus $0.25 /mi traveled during that week. An equation
...
esent the cost would be y=46+0.25x , where x is the number of miles traveled.
a. What is your cost if you travel 59 mi?
The cost is $
43.26
.
b. If your cost was $66.25 , how many miles were you charged for traveling?
You were charged for traveling
66.51
miles.
c. Suppose you have a maximum of $100 to spend for the car rental. What would be the maximum number of miles you could travel?
The maximum number of miles you could travel is
Number
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7.3A(g) + X(g) → Z(g) ΔH° = -480 kJ/molrxn
The equation shown above represents an exothermic reaction between A(g)
...
reaction between A(g) and X(g). What is the amount of heat released when 10 mol of A(g) reacts with an excess X(g) ?
ΔH
A -236kJ
X -136kJ
Y -167kJ
Using the heats of formation found in the table above, calculate ΔH for the reaction below.
6A(aq) + 7X(g) → 6Y(l)
Y + 2X → 4Z ΔH=-4
A + 3B → 2Z ΔH=-2
A → X +C ΔH=7
Using the thermodynamic data above, determine ΔH for the reaction below.
2C+ 6B → Y
When 0.3 moles of A(s) (4 grams) is dissolved in 12 grams of water at 23°C, the temperature of the water increases to 31°C. The specific heat of water is 4.18 J/g°C.
Calculate ΔH in kJ/mol. Report your answer to 1 decimal place.
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12.AP Chem AB FRQ
Question 1
A sample consisting of 50. mL of 0.400 M solution of the acid, HClO4, is titrated
...
titrated with a 0.200 M solution of the base, LiOH.
Write the balanced chemical reaction for neutralization reaction:
HClO4 (aq) + LiOH (aq) → LiClO4 (aq) + H2O (l)
Write the NET ionic equation for the neutralization reaction.
OH⁻ (aq) + H⁺ (aq) → H2O (l)
Compute the pH of the titration solution. Show your work
i) before any of the base is added
ii) after 25. mL of base is added
iii) after 50. mL of base is added
A student performs the titration with the same chemicals but with smaller volumes of each chemical . Which of the following titration curves could represent the titration. Explain
A because this entails a strong acid and a strong base.
Question 2
A student performs a titration of an unknown acid with a strong base and gets the following titration curve:
a) The student consults the list of pKa of acids shown below. If the acid is listed in the table below, which is the most likely identity of the unknown acid? Explain.
Acid
Ka
HF
7.2 x 10-4
CH3COOH
1.8 x 10-5
H2CO3
4.3 x 10-7
HBrO
2.0 x 10-9
The unknown acid is HBrO because the calculated Ka is in between 50^-4 and 50^-6 and 2.0 x 10^-9 lies in between them.
b) What is the initial molarity of the acid?
10^-3 = 0.001M
Question 3
a) Describe the components and the composition of an effective buffer solution. Explain how the components of the buffer allow the buffer to maintain its pH.
An effective buffer solution has a weak acid and its conjugate base or a weak base and its conjugate acid. A buffer solution is most effective when the ratio of its component concentrations is close to 1, also when the pH is equal to the pka of the acid.; The components of the buffer allow the buffer to maintain its pH because buffers can absorb excess H+ions or OH– ions.
An employer is interviewing four applicants for a job as a laboratory technician and asks each how to prepare a buffer solution with a pH of 5.0. The following constants may be helpful: hydrazoic acid, pKa = 4.74 Boric acid, pKa = 9.23
Archita A. says she would mix equal molar solutions of hydrazoic (HN3) and sodium azide (NaN3) solutions.
Bradley B. says she would mix equimolar Boric acid (H3BO3) and HCl solutions.
Carlos C. says he would mix equimolar Boric Acid (H3BO3) and sodium dihydrogen borate (NaH2BO3) solutions.
Delia D. says he would mix equimolar hydrazoic Acid (HN3) and NaOH solutions.
b) Which of these applicants has given an appropriate procedure? Explain your answer
Delia because she is using Sodium hydroxide which results in a pH of 5. NaOH is a strong base and in order to have an effective buffer a weak acid must be incorporated which is the HN3.
c) Explain what is wrong with the erroneous procedures.
The rest all incorporate a strong acid and a strong base or a weak acid and a weak base which don’ result in an effective buffer.
d) The applicants have access to the 1 Liter volumes of each of the solutions listed above. They have access to graduated cylinders. In order to make 1.0 Liter of the correct 5.0 buffer solution, what volumes of the two chemicals must be mixed?
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14.I am trying to figure out the optimal radius that will give the lowest surface area of a cylinder. I
...
have done the calculus which reveals that the surface area is at a minimum when height is double the radius. I am now trying to find an equation for the relationship between the amount of wasted surface area as a percentage of the minimum surface area and the ratio between height and radius.
If I were to plot it on a graph, the y axis would be the percentage of excess materials needed as a percentage of the minimum possible surface area, and the x axis would be height divided by radius. Since the surface area is minimized when height=2(radius), I know that when x=2, y=0.
The website https://www.datagenetics.com/blog/august12014/index.html explains what I am trying to do quite well and shows the graph below. I am trying to find the equation for this graph, but am unsure how to go about it.
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16.At a price of $1.04 per roll, the supply of toilet paper in a large town is 25,000 rolls, and
...
mand is 18,200 rolls. When the demand increases to 26,200 rolls, the supply is 20,000 and the price is $1.24 per roll. Let x be the quantity in thousands of rolls. The table below gives the price-supply and price-demand equations.
Price Equations for Toilet Paper
Type Equation
Price-Supply P = -0.04x + 2.04
Price-Demand P = 0.025x + 1.495
QUESTION 1
Find the supply at a price of $2 per roll.
1000 rolls
10,000 rolls
1 roll
5000 rolls
QUESTION 2
Find the demand at a price of $2 per roll.
20.2 rolls
202 rolls
20,200 rolls
500 rolls
QUESTION 3
Use the substitution method to find the equilibrium quantity. Round x to the nearest tenth first and then convert to thousands. Include the units in your answer.
QUESTION 4
What is the equilibrium price? Write the answer in dollars and cents, rounding to the nearest cent.
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19.Directions: You are part of a fireworks crew assembling a local fireworks display.
There are two parts to the fireworks platforms:
...
rts to the fireworks platforms: one part is on the ground and the
other part is on top of a building. You are going to graph all of your results on one
coordinate plane. Make sure to label each graph with its equation. Use the following
equations to assist with this assignment.
• The function for objects dropped from a height where t is the time in
seconds, h is the height in feet at time it t, and 0 h is the initial height is
2
0 ht t h ( ) 16 =− + .
• The function for objects that are launched where t is the time in seconds, h is
the height in feet at time t, 0 h is the initial height, and 0 v is the initial velocity
in feet per second is 2
0 0 ht t vt h ( ) 16 =− + + .
Select the link below to access centimeter grid paper for your portfolio.
Centimeter Grid Paper
Task 1
First, conduct some research to help you with later portions of this portfolio
assessment.
• Find a local building and estimate its height. How tall do you think the
building is?
• Use the Internet to find some initial velocities for different types of fireworks.
What are some of the initial velocities that you found?
Task 2
Respond to the following items.
1. While setting up a fireworks display, you have a tool at the top of the
building and need to drop it to a coworker below.
a. How long will it take the tool to fall to the ground? (Hint: use the first
equation that you were given above, 2
0 ht t h ( ) 16 =− + . For the building’s
height, use the height of the building that you estimated in Task 1.)
b. Draw a graph that represents the path of this tool falling to the
ground. Be sure to label your axes with a title and a scale. Your graph
should show the height of the tool, h, after t seconds have passed.
Label this line “Tool”.
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21.I'm stuck on this problem regarding finding the speed of a cart moving down and then up a slope from
...
rest. The current unit that our teacher has us on so far is centripetal motion, and I can't recall being taught how to solve this. File attached below shows my work so far, I don't necessarily need the work done for me, but I just want to be put on the right track, such as an equation to start with or what I need to look for. The answer I got was clearly incorrect for part a (which is what I need help with), so please help me get going in the right direction.
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23.I have 5 questions I am stuck on. Please help!
1. Enter the correct answer in the box.
Facundo crochets and sells
...
chets and sells baby blankets, b. Each blanket requires 3 skeins of yarn, and the total number of skeins Facundo uses, y, varies directly as the number of blankets he crochets, b.
Write an equation that models this relationship.
2. The weight of an object, w, varies inversely as the square of its distance from the center of Earth, d. When an astronaut stands in a training center on the surface of Earth (3,960 miles from the center), she weighs 155 pounds. To the nearest tenth of a pound, what will be the approximate weight of the astronaut when she is standing on a space station, in orbit 240 miles above the training center?
3. The square of g varies inversely as h. When g = 16, h = 2. What is the value of h when g = 40?
4. The number of days, d, it will take Manny to read a book varies inversely as the number of pages, p, he reads per day. If k is the constant of variation, which equation represents this situation?
5. The battery life for Bruhier’s cell phone is longer when he has fewer apps running. When only one app is running, the battery will last for 16 hours. When four apps are running, the battery will only last for 4 hours.
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27.After a dreary day of rain, the sun peeks through the clouds and a rainbow forms. You notice the rainbow
...
nbow is the shape of a parabola.
The equation for this parabola is y = -x2 + 36.
Graph of a parabola opening down at the vertex 0 comma 36 crossing the x–axis at negative 6 comma 0 and 6 comma 0.
Create a table of values for a linear function. A drone is in the distance, flying upward in a straight line. It intersects the rainbow at two points. Choose the points where your drone intersects the parabola and create a table of at least four values for the function. Remember to include the two points of intersection in your table.
Analyze the two functions. Answer the following reflection questions in complete sentences.
What is the domain and range of the rainbow? Explain what the domain and range represent. Do all of the values make sense in this situation? Why or why not?
What are the x- and y-intercepts of the rainbow? Explain what each intercept represents.
Is the linear function you created positive or negative? Explain.
What are the solutions or solution to the system of equations created? Explain what it or they represent.
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28.Hi, I've been trying to figure out what should be the simplest of formulas for over an hour now. Take
...
e a look at this spreadsheet so I can properly explain:
https://docs.google.com/spreadsheets/d/1lEJIPiSZJk9LYUTSA4oeDwyLXCVd18Zdewm6gnjxcXo/edit?usp=sharing
Ok, so for the sake of simplicity We'll just go with row two here. Cell A2 represents the hours worked freelancing, where B2 is for the minutes of the recorded time frame. C2 is the net amount earned in that time. Over in cell N10 I need to figure out an equation using the =SUM() function (treats it as a normal math problem) where it prints the hourly income based on those three integers. I'll admit i was never great at math, but in my defense I've been up since 6 am yesterday (currently 3 pm) and have been running solely on caffiene and nicotine haha... The sheet is editable and I can see any changes you make in realtime. Is there any way you could help me out on this one? It's for a work report type thing.
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34.
For a reducing balance loan what happens when you pay a extra repayments aggressively at the start. How does it
...
rt. How does it make u pay less interest and have less interest:
Vn+1 = 1.00405Vn - 1817.35, Vo= 34400
The term of the loan is 30 years with monthly payment of 1817.35 at an interest rate of 4.86 p.a
Pls tell me the answer regarding this particular equation
Q2) How much of the principal has been repaid? Fv - Vo is this the correct formula
Q3) Superannuation
Something like if u add money without tax why does it benefit your super account
I’m sorry to disturb you but I was hoping you could help as tmrw is my last writing lesson for my sac
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39.I am looking for someone who is used to water resources engineering/fluid dynamics. I have been tasked to design the
...
ed to design the water, wastewater, and stormwater systems for an addition to a building at our university. I have the maps of the existing systems and I am planning to use these existing systems as much as possible to avoid extra work. I have calculated a water demand and fire flow for the building. I believe I have to use mannings equation for the water pipes to determine flow, etc. I am not sure how to deal with the wastewater. I have to use the rational method for stormwater. I have attached a document which explains what I need to do overall. I need help on this ASAP as I have to present it Tuesday evening.
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40.A quarterback throws a football. The height, h metres, of the ball is given by the equation h = −5t2
...
t2 + 20t +2 where t is the time in seconds after the ball is thrown.
a) Graph the equation using desmos (if you can take a screen shot of it and include it)
b) Why do we use only positive values of h and t?
c) What is the height of the ball 1 second after it is thrown?
d) What is the maximum height of the ball?
e) How long does it take for the ball to reach the maximum height?
f) For how long is the ball more than 10 m above the ground?
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42.I was wondering if you could help me step up my chem problems, i'm not sure how to begin
...
estion 1: Draven collected a 1ml sample from a local river. Draven added 99 ml of water to the sample. Draven then took 5 ml of the diluted sample, and determined the 5 ml sample to contained 10 mg of sodium chloride. what is the concentration of sodium chloride in the river?
question 2: how many grams of H2 could be produced when 13 g of H202 decompose?
question 3: how many molecules of carbon dioxide could be produced when 25 ml of a 0.8 M ethanol, c2h60, combusts with 5.18X10^23 molecules of oxygen? the unbalanced equation for the combustion of ethanol is given below:
2ch6O+302-> c02+h20
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43.2. If the mean of the numbers 9, 10, 11, 12, and x is 12, what is the value
...
s of a sports drink contains 130 milligrams of sodium, what is the total number of milligrams of sodium in 20 ounces of the sports drink?
5. If (k, 3) is a point on the line whose equation is 4x + y = -9, what is the value of k?
9. A flagpole casts a shadow 200 feet long. At the same time, a boy standing nearby who is 5 feet tall casts a shadow 20 feet long. Find the number of feet in the height of the flagpole.
22. What is the greatest value of c for which the roots of the equation x^2 + 4x + c = 0 are real?
24. Find the two acute angles in the right triangle whose sides have the given lengths. Express your answers using degree measure rounded to two decimal places.
7, 24 and 25
A._________________ (smaller value)
B._________________ (larger value)
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44. 1. What is the greatest value of c for which the roots of the equation x^2 + 4x +
...
2. Find the two acute angles in the right triangle whose sides have the given lengths. Express your answers using degree measure rounded to two decimal places.
A._______________________ (Smaller Value)
B. _______________________ (Larger Value)
3. A flagpole casts a shadow 200 feet long. At the same time, a boy standing nearby who is 5 feet tall casts a shadow 20 feet long. Find the number of feet in the height of the flagpole.
4. If (k, 3) is a point on the line whose equation is 4x + y = -9, what is the value of k?
5. If 8 ounces of a sports drink contains 130 milligrams of sodium, what is the total number of milligrams of sodium in 20 ounces of the sports drink?
6. If the mean of the numbers 9, 10, 11, 12, and x is 12, what is the value of x?
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45.
Value: 1
equation image indicator
a. (x - 2)2(x - 3)2
b. (x2+ 4)(x2+ 9)
c. (x - 2)(x +
...
2)(x - 3)(x + 3)
d. (x2 - 4)(x2+ 9)
Value: 1
The table below shows the cost of purchasing a standard stapler at five office supply stores, A through E. If the median cost of purchasing a standard stapler for these stores was $17.99, which of the following could NOT have been the cost of the stapler for Store A?
staplergraph.jpg
a. $19.95
b. $18.95
c. $16.95
d. $19.25
Value: 1
If equation image indicator then x =
a. 7
b. 1/5
c. 5
d. 1/7
Value: 1
A six−sided die, with sides numbered 1,2, 3,4,5, and 6, is tossed. What is the probability of tossing a number less than three?
a. 1/3
b. 0
c. 1/2
d. 1/4
Value: 1
If 6m + 4 = 8m, then 4m =
a. 6
b. 2
c. 8
d. 4
Value: 1
In the xy-plane, what is the y-intercept of the graph of the equation equation image indicator?
a. 2
b. 4
c. 16
d. There is no y-intercept.
Value: 1
Which of the following equations has both 2 and −4 as solutions?
a. x2 + 6x + 8 = 0
b. x2 - 2x - 8 = 0
c. x2 + 2x - 8 = 0
d. x2 - 2x + 8 = 0
Value: 1
The perimeter of a square is 20 ft. If you increase the length of the square by 2 feet and decrease the width by 1 foot, what is the area, in square feet, of the new figure?
a. 22
b. 28
c. 35
d. 40
Value: 1
(3x-2y4)-3 =
a. equation image indicator
b. equation image indicator
c. equation image indicator
d. equation image indicator
Value: 1
A softball is tossed into the air upward from a first floor balcony. The distance of the ball above the ground at any time is given by the function, distance function.png, where h(t) is the height of the softball above the ground (in feet) and t is the time (in seconds). What was the maximum height, in feet, of the softball above the ground after it was thrown?
a. 28
b. 30
c. 32
d. 34
Value: 1
A group of 100 people, some students and some faculty, attended a museum opening. Each student paid $10 per person for entrance to the museum and each of the faculty paid $25 per person for entrance. If the total paid, for all 100 people, was $1300, how many students attended the museum opening?
a. 20
b. 50
c. 70
d. 80
Value: 1
The ratio of Sam's age to Hank's age is 5 to 3. If the sum of their ages is 24, how old is Hank?
a. 21
b. 15
c. 19
d. 9
Value: 1
In the xy−coordinate plane shown below, point P has coordinates (8, −6). Which of the following is an equation of the line that contains points O and P?
O and P graph.jpg
a. equation image indicator
b. equation image indicator
c. equation image indicator
d. equation image indicator
Value: 1
The variables x and y are inversely proportional, and y = 2 when x = 3. What is the value of y when x = 9?
a. 54
b. 6
c. 2/3
d. 3/2
Value: 1
A farmer has 1235 trees to be planted on a rectangular parcel of land. If there are 24 trees planted in each row and each row must be complete before it is planted, how many trees will be left over after planting?
a. 21
b. 11
c. 0
d. 55
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46.I investigated a relationship about the daily profit from renting tubes at Water World. The equation that models profit earned
...
that models profit earned is D = n(54 – n) – 10n. I need to find the vertex of this equation, and what does the vertex tell me about this situation.. For what x-values is the function increasing? Decreasing? What does this mean in terms of daily profit for Water World? Rewrite the function in vertex form. . Solve the equation 0 = n(54 – n) – 10n for n. Describe your solution method. How are the solutions from part (e) related to the graph of this function? Are the solutions real or complex? How do you know? What do the solutions from part (e) tell you about this situation?
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