# SARAH

Popular questions and responses by SARAH-
## Physics

A 1000 kg car pushes a 2000 kg truck that has a dead battery. When the drive steps on the accelerator, the drive wheels of the car push against the ground with a force of 4500 N. a) What is the magnitude of the force of the car on the truck? b) what is the

*asked on June 12, 2010* -
## GEOMETRY HELP PLEASE

The bases of trapezoid $ABCD$ are $\overline{AB}$ and $\overline{CD}$. We are given that $CD = 8$, $AD = BC = 7$, and $BD = 9$. Find the area of the trapezoid.

*asked on April 23, 2016* -
## Physics

A grasshopper leaps into the air from the edge of a cliff at a 50 degree angle. He reaches a maximum height 6.74 cm above the top of the cliff and travels a total horizontal distance of 1.06 m. How tall is the cliff and what is the initial speed of the

*asked on June 12, 2015* -
## Chemistry

Identify the products formed in this Brønsted-Lowry reaction. HPO2−4+HBrO↽−−⇀acid+base Acid: Base:

*asked on July 30, 2019* -
## physics

It is possible to shoot an arrow at a speed as high as 100 m/s. (a) If friction is neglected, how high would an arrow launched at this speed rise if shot straight up? (b) How long would the arrow be in the air? Please help! I do not have any clue as to how

*asked on June 7, 2010* -
## Physics

The four tires of an automobile are inflated to an absolute pressure of 2.0*10^5 Pa. Each tire has an area of 0.024m^2 in contact with the ground. Determine the weight of the automobile. Pressure*area= force. There are four tires.

*asked on May 10, 2007* -
## physics

What is the tension in the rope of this figure description? 60 kg person is hanging in the air on a rope attached to a pulley, with a 100 kg mass attached on other end that is touching the ground.

*asked on June 13, 2010* -
## Physics

2. Consider the ball example in the introduction when a ball is dropped from 3 meters. After the ball bounces, it raises to a height of 2 meters. The mass of the ball is 0.5 kg a. What is the speed of the ball right before the bounce? b. How much energy

*asked on November 5, 2015* -
## Physics

A potter’s wheel with rotational inertia of 45 kg m2, is spinning freely at 40 rpm. The potter drops a lump of clay onto the wheel where it sticks a distance 1.2 m from the rotational axis at the wheel’s center. If the subsequent angular speed of the

*asked on June 29, 2009* -
## History

Which battle was a major turning point for US and South Korean forces during the Korean War? a. Battle of Pork Chop Hill b. Spring Offensive c. Battle of Heartbreak Ridge d. Inchon Bay landing Is it D?

*asked on August 20, 2018* -
## Physics

A tennis player hits a ball at ground level, giving it an initial velocity of 24 m/s at 57 degrees above the horizontal. (a) what are the horizontal and verticla components of the ball;s initial velocity? (b) how high above the ground does the ball go? (c)

*asked on June 7, 2009* -
## History

Which accurately describe the causes of the contentious relationship between President Truman and General MacArthur? (Select all that apply.) a. Truman favored a containment policy on Communism, while MacArthur wanted to pursue the Communist forces into

*asked on August 20, 2018* -
## Calculus!!!

Find f. (Use C for the constant of the first antiderivative and D for the constant of the second antiderivative.) f ''(x) = 8 + x3 + x5

*asked on November 7, 2013* -
## Physics

The launching mechanism of a toy gun consists of a spring of unknown spring constant, as shown in Figure P5.33a. If its spring is compressed a distance of 0.140 m and the gun fired vertically as shown, the gun can launch a 24.0 g projectile to a maximum

*asked on June 16, 2011* -
## Physics

a model of a helicopter rotor has four blades, each 3.40 m in length from the central shaft to the tip of the blade. The model is rotated in a wind tunnel at 550 rev/min. A) what is the linear speed, in m/s of the blade tip? B.) what is the radial

*asked on June 7, 2009* -
## Economics

Questions: Are the following workers more likely to experience short-term or long-term unemployment? Explain. a. A construction worker laid off because of bad weather. b. A manufacturing worker who loses her job at a plant in an isolated area. c. A

*asked on March 24, 2007* -
## Chemistry

What is the total volume of gases produced at 819 K and 1. atm pressure when 320 g of ammonium nitrite undergoes the following decomposition reaction? NH4NO2 --------> N2(g) + 2H2O(g)

*asked on November 14, 2012* -
## physics

A certain orthodontist uses a wire brace to align a patient's crooked tooth as in the figure below. The tension in the wire is adjusted to have a magnitude of 21.12 N. Find the magnitude of the net force exerted by the wire on the crooked tooth.

*asked on October 5, 2011* -
## college physics

three carts of masses 4.0kg, 10kg, and 3.0kg move on a frictionless horizontal track with speeds of 5.0m/s, 3.0m/s, and 4.0m/s. The carts stick together after colliding. find the velocity of the three carts.

*asked on June 1, 2008* -
## Calculus

The monthly demand function for a product sold by a monopoly is p = 3750 − 1/3x^2 dollars, and the average cost is C = 1000 + 70x + 3x^2 dollars. Production is limited to 1000 units and x is in hundreds of units. (a) Find the quantity that will give

*asked on March 25, 2013* -
## physics

the speed of the fastest pitched baseball was 45 m/s, and the ball's mass was 145 g. (a) What was the magnitude of the momentum of this ball, and how many joules of kinetic energy did it have? (b) How fast would a 57 gram ball have to travel to have the

*asked on October 28, 2009* -
## Trig

Cosine theta=8/17 and 270 degrees is < theta, and theta is< 360

*asked on September 28, 2016* -
## PHYSICAL SCIENCE

A 1.0 kg metal head of a geology hammer strikes a solid rock with a velocity of 5.0 m/s. Assuming all the energy is retained by the hammer head, how much will its temperature increase?

*asked on November 2, 2007* -
## Calculus

A landscape architect wished to enclose a rectangular garden on one side by a brick wall costing $60/ft and on the other three sides by a metal fence costing $50/ft. If the area of the garden is 102 square feet, find the dimensions of the garden that

*asked on April 9, 2016* -
## math

A recipe that makes 18 cookies calls for 3/4 cup of sugar. How much sugar is needed to make 24 cookies using this recipe?

*asked on March 3, 2011* -
## Physics

When a driver applies brakes to keep a car going downhill at constant speed and constant kinetic energy, the potential energy of the car decreases. Where does this energy go? Where does most of it appear in a hybrid vehicle?

*asked on January 2, 2011* -
## phyics

Cheryl is riding on the edge of a merry-go-round, 2m from the center, which is rotating with an increasing angular speed. Cheryl’s tangential acceleration is 3.0m/s2. At the instant that Cheryl’s linear speed is 4.0m/s, what is Cheryl’s total

*asked on November 29, 2015* -
## english

Which of the following is the best definition of a drama? a. a story with props b. a story with a happy ending c. a story written to be preformed by actors d. a story in which the main character eventually fails I think it's D, can anyone check me? Thanks

*asked on April 11, 2015* -
## math

Convert the base-ten number to a numeral in the indicated base. 329 to base six

*asked on July 20, 2009* -
## Mathematics

A closed tin of milk has diameter 10cm and height 16cm find the total surface area of the tin( take pie to be 22/7

*asked on June 18, 2020* -
## biology

Which best describes Francis Bacon’s contribution to the Scientific Revolution?

*asked on February 27, 2018* -
## PHYSICS

A 200g block slides back and forth on a frictionless surface between two springs, as shown. The left-hand spring has k = 130 N/m and its maximum compression is 16cm. The right-hand spring has k = 280 N/m. Find (a) the maximum compression of the right-hand

*asked on February 12, 2014* -
## math

seven horses are entered in a race. If two horses are tied for first place, and there are no ties among the other five horses, in how many ways can the seven horses cross the finish line?

*asked on May 6, 2016* -
## Pre-calculus

Complete the table assuming continuously compounded interest. (Round your answers to two decimal places.) Initial Investment: Annual % Rate: Time to Double: 8 yr Amount After 10 Years: $1700 I don't understand how to get in the initial investment of annual

*asked on October 11, 2015* -
## physics

A child is standing on a platform of a station. A train travelling at 30m/s takes 3.0 secs to pass the child.What is the length of the train. a)10m-this was my answer b)27m c)30m d)90m

*asked on November 9, 2014* -
## Physics

The engine of a motorboat delivers 30.0 kW to the propeller while the boat is moving at 15.0m/s. What would be the tension in the towline if the boat were being towed at the same speed? I know to use P=Fv and solve for F so P = 3000kN right because 1 kW =

*asked on June 22, 2009* -
## physics

Does the KE of a car change more when it goes from 10 to 20 km/h or when it goes from 20 to 30 km/h?

*asked on March 2, 2009* -
## Math

The perimeter of rectangle P is 12 feet. The perimeter of rectangle Q is 18 feet. Both rectangles have the same area.Find the area and dimensoin of each rectangle.

*asked on April 20, 2011* -
## Language Arts

In the multi-draft reading process what does a reader look for in the third reading? *This is a question from Connexus, and I really need help D:

*asked on April 9, 2015* -
## Civics

2. One main difference between the United States Constitution and state constitutions is that state constitutions A. are much longer. B. don't provide for a legislature. C. can't be amended. D. don't have bills of rights. So your saying it's D? (Reed)

*asked on March 29, 2015* -
## Literature

What are some of the poetic devices used in this poem by Gladys Cardiff? -diction -end-stopped -lyric -symbol -syntax Bending, I bow my head And lay my hand upon Her hair, combing, and think How women do this for Each other. My daughter's hair Curls

*asked on January 12, 2011* -
## Calculus

If tanh(x)=24/25, find the values of the other hyperbolic function at x I was able to find coth(x)=25/24, but what is sin, cos, csc, and sec? I would greatly appreciate your help!!

*asked on May 24, 2010* -
## chemistry

draw the skeletal structure line-angle (line-bond) mode of 2-isopropyltoluene. Identify the number of hydrogen atoms bound to each carbon in the structure.

*asked on October 13, 2016* -
## Statistics

The probability that a randomly selected individual in a certain community has made an online purchase is 0.45. Suppose that a sample of 10 people from the community is selected, what is the probability that at most 3 of them has made an online purchase?

*asked on June 2, 2013* -
## MSU

aluminum sulfate and sodium phosphate Express your answer as chemical equation.

*asked on October 6, 2011* -
## Physical Science

A cylinder of acetylene gas is kept at a temperature of 291K. The pressure in the cylinder is 5atm. This cylinder can withstand a pressure of 8atm before it explodes. What is the maximum temperature that the cylinder can safely be stored at ?

*asked on July 1, 2020* -
## Chemistry

If you weigh out 2.083 g Fe(NO3)3·9H2O, what is the final concentration of the dilute Fe(NO3)3 solution that you make?

*asked on June 27, 2013* -
## Chemistry

Commercial vinegar was titrated with NaOH solution to determine the content of acetic acid, HC2H3O2. For 20.0 milliliters of the vinegar 26.7 milliliters of 0.600-molar NaOH solution was required. What was the concentration of acetic acid in the vinegar if

*asked on May 23, 2007* -
## Chemistry

You have 75.0 mL of a 2.50 M solution of Na2CrO4 (aq). You also have 125 mL of a 2.15 M solution of AgNO3 (aq). Calculate the concentration of NO3 when the two solutions are added together.

*asked on August 22, 2015* -
## Algebra

an investment of 72,000 was made by a business club. the investment was split into three parts and lasted for one year. the first part of the investment earned 8% interest. the second 6% and the third 9%. total interest from the investments was $5640. the

*asked on March 9, 2011* -
## Enthalypy Reaction

What is the standard enthalpy of reaction for the following chemical reaction? CO2(g) + 2KOH(s) --> H2O(g) + K2CO3 (s) Express your answers numerically in kJ.

*asked on September 23, 2008* -
## chemistry

What is the mass of 225ml of a liquid that has a density of 0.880g/ml

*asked on September 4, 2015* -
## SCIENCE HELP PLEASE

Suppose the moon rotated on its axis just as quickly as Earth. Would you still always see the same side of the moon from Earth? *HELP ME PLEASE*

*asked on January 8, 2014* -
## probability

For a family with 2 children, the sample space indicating boy (B) or girl (G) is BB, BG, GB, and GG. If each of the outcomes is equally likely, find the probability that the family has 2 girls, given that the first child is a girl.

*asked on July 6, 2013* -
## World Geography

Imagine you are an elected official with the responsibility of drafting legislation designed to protect our environment. What items will you include in your bill? Who will be responsible for the bill's implementation? Its enforcement? Your response should

*asked on March 6, 2014* -
## Chemistry

What is the value of q when 8.21g of water vaporizes at 373 K? The enthalpy of condensation of water at 373 K is -40.7 kJ/mol. I tried using the equation q= m x Cs x Delta T, but I never got the right answer which is 18.5 kJ apparently, so I need to find

*asked on February 4, 2013* -
## Chemistry 20

which of the following indicators would show an intermediate endpoint of color of orange: bromocresol green, methyl red, phenolphthalein or methyl violet? No clue how to do this. And what does it mean to show an intermediate endpoint. Please help

*asked on December 14, 2017* -
## Civics

1. Suppose Bill HR612 is currently in Congress. One thing you know about this bill is that it A. originated in the House of Representatives. B. has been vetoed by the president. C. has no riders attached. D. is currently in committee. A?

*asked on March 29, 2015* -
## math

In a certain town, 25% of people commute to work by bicycle. If a person is selected randomly from the town, what are the odds against selecting someone who commutes by bibycle? A). 3:1 B). 3:4 C). 1:3 D). 4:1

*asked on September 18, 2010* -
## chemistry

Nucleophile or electrophile? (1) CH3COOH (2) CH3COO- At first, I thought that they were both Nucleophiles, but now Ive confused myself and Im not sure.. Please help!

*asked on October 5, 2009* -
## Chemistry

The thermal decomposition of 1.6608 g of MgSO4 * H2O produces 1.4446 g of a product in a well-behaved reaction. There are two possibilities: 1) MgSO4 * H2O(s) -> MgSO4(s) + H2O(g) 2) MgSO4 * H2O(s) -> MgO(s) + SO3(g) + H2O(g) Complete the following table,

*asked on February 10, 2018* -
## Chem

Consider the following balanced equation: 2N2H4(g)+N2O4(g)→3N2(g)+4H2O(g) Complete the following table showing the appropriate number of moles of reactants and products. If the number of moles of a reactant is provided, fill in the required amount of the

*asked on April 27, 2016* -
## Civics

6. If both the president and the vice president are unable to fulfill their duties, who takes over as president? A. President pro tempore of the Senate B. Attorney general C. Speaker of the House D. Secretary of state "In the case that the president can no

*asked on April 3, 2015* -
## finance

A firm has beginning inventory of 300 units at a cost of $11 each. Production during the period was 650 units at $12 each. If sales were 700 units, what is the cost of goods sold (assume FIFO)?

*asked on February 7, 2010* -
## Physics

The speed of sound in steel is 5000 m/s. What is the wavelength of the sound wave of 640 Hz in steel?

*asked on June 29, 2009* -
## Physics

a 65-kg ice skater moving to the right with a velocity of 2.50m/s throws a .150kg snowball to the right with a velocity of 32.0m/s relative to the ground a) what is the velocity of the ice skater after throwing the snowball? b) a second skater initially at

*asked on April 26, 2012* -
## AP Physics PLEASE HELP DUE TOMORROW

Consider the freight train. Suppose 15 boxcars pass by in a time of 14.0 s and each has a length of 14.0 m. (a) What is the frequency at which each boxcar passes? (b) What is the speed of the train?

*asked on February 8, 2011* -
## science

How many neutrons does the most common isotope of carbon contain? Use the diagram below to help you.

*asked on July 6, 2020* -
## Calc

If y=tanu, u=v-(1/v), and v=lnx. What is the value of dy/dx at x=e?

*asked on December 6, 2016* -
## Physics

A diver leaves a 3-m board on a trajectory that takes her 2.8m above the board and then into the water 2.7m horizontally from the end of the board.At what speed and angle did she leave the board?

*asked on March 26, 2015* -
## Chemistry

Which one of the following liquids will have the highest freezing point? A. pure H2O B. aqueous glucose (0.050 m) C. aqueous CoI2 (0.030 m) D. aqueous FeCl3 (0.030 m) E. aqueous NaI (0.030 m) Could you please give a step by step process?

*asked on November 7, 2011* -
## Calc.

Please help solve this, A farmer has 600m of fence and wants to enclose a rectangular field beside a river. Determine the dimensions of the fence field in which the maximum area is enclosed. (Fencing s required on only three sides: those that aren't next

*asked on March 2, 2010* -
## Partial Pressure- Chemistry

A gaseous mixture of O2 and N2 contains 31.8 % nitrogen by mass. What is the partial pressure of oxygen in the mixture if the total pressure is 445 mmHg?

*asked on September 23, 2008* -
## Algebra

A chemist wishes to mix a solution that is 4% acid. She has on hand 66 liters of a 2% acid solution and wishes to add some 8% acid solution to obtain the desired 4% acid solution. How much 8% acid solution should she add? There is a chart

*asked on May 22, 2016* -
## Biology

Is 9th grade biology hard? Is it interesting...?? I love life science but I just wondering if 9th grade biology hard??? I'm taking biology next year.

*asked on April 29, 2013* -
## physics

an experimental rocket plane lands on skids on a dry lake bed. it is traveling at 80.0 m/s when it touches down, how far does it slide before it comes to a stop? assume the coeffcient of kinetic friction between the skids and the lake is .600

*asked on March 5, 2012* -
## Physics

In the figure, a chain consisting of five links, each of mass 0.100 kg, is lifted vertically with constant acceleration of magnitude a = 2.50 m/s2. Find the magnitudes of (a) the force on link 1 from link 2, (b) the force on link 2 from link 3, (c) the

*asked on March 19, 2011* -
## Physics

A bowling ball weighing 71.2 N is attached to the ceiling by a 3.80 m rope. The ball is pulled to one side and released; it then swings back and forth like a pedulum. as the rope swings through its lowest point, the speed of the bowling ball is measured at

*asked on June 15, 2009* -
## Physics

A Chinook salmon can jump out of water with a speed of 6.60 m/s . How far horizontally d can a Chinook salmon travel through the air if it leaves the water with an initial angle of θ=27.0° with respect to the horizontal? (Let the horizontal direction the

*asked on September 6, 2018* -
## Chemistry

From the lewis structure of AlCl4- where should I place the formal charge? next to Al or Cl?

*asked on December 5, 2010* -
## Physics

A bullet of mass 45 g is shot at a speed of 220 m/s into a 5.0-kg bag hanging from a string from the ceiling. The bag absorbs the bullet and begins to swing. To what maximum vertical height will it rise? Hint: Energy is not conserved as the bullet enters

*asked on November 24, 2010* -
## Chemistry

The reaction of aqueous sodium bromide and aqueous lead(II) nitrate is represented by the balanced net ionic equation. 2Br-(aq) + Pb2+(aq) → PbBr2(s) Give the balanced ionic equation for the reaction. Include the states.

*asked on January 29, 2010* -
## Math

2. The cost of producing x units of a certain commodity is given by Px 1000 0 x MCsds, where P is in dollars and Mx is marginal cost in dollars per unit. A. Suppose the marginal cost at a production level of 500 units is $10 per unit, and the cost

*asked on September 1, 2019* -
## Civics

The _______ form of city government merges executive and legislative functions in a single group of officials. A. township B. commission C. mayor-council D. city manager C?

*asked on April 3, 2015* -
## AP Calculus

Find all points on the graph of f(x)=-x^3+3x^2-2 where there is a horizontal tangent line.

*asked on November 30, 2014* -
## Statistics

The probability that a student uses the Academic Resource Center on a regular basis is 0.26. In a group of 18 students, what is the probability that exactly 8 of them use the Academic Resource Center on a regular basis? Round your answer to 2 decimal

*asked on June 2, 2013* -
## Chemistry Help

What is the ionic equation for: 2 HClO4(aq) + Mg(OH)2(s) ¨ Mg(ClO4)2(aq) + 2 H2O(l)

*asked on December 18, 2010* -
## Chemistry

Electromagnetic radiation with a wavelength of 665 nm appears as orange light to the human eye. The energy of one photon of this light is __________ J.

*asked on October 26, 2010* -
## Calc.

If the Queen Bee leaves the hive and travels 210 m [N32°E] and then 37 m [S51°W], how far and in what direction is the bee from its hive? I am unsure of my final answer, can someone please explain this so I know if I am doing this right? THANKS!

*asked on July 2, 2008* -
## Economics

7. Suppose there are two possible income distributions in a society of ten people. In the first distribution, nine people have incomes of $30,000 and one person has an income of $10,000. In the second distribution, all ten people have incomes of $25,000.

*asked on March 8, 2007* -
## Chemistry

Write a net ionic equation for the reaction that occurs when excess hydrobromic acid (aq) and sodium sulfide are combined.

*asked on September 24, 2017* -
## English

Roosevelt is arguing that journalists must only attack misconduct when they have valid proof. They must not dig just for the sake of digging; it is offensive to good Americans. Which statement most effectively argues against this claim? a) Even sensational

*asked on March 8, 2016* -
## Drama

In act 1 scene 2 of a christmas carol scrooge and marley, why does scrooge object to people enjoying christmas?

*asked on April 13, 2015* -
## Math

A drawer contains 22 black socks, 22 white socks, and 22 blue socks. If the light is off and Matt reaches into the drawer to get his socks, what is the minimum number of socks he must pull out in order to be sure that he has a matching pair?

*asked on January 17, 2015* -
## Physics

A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0° above the horizontal. How long is she in the air before returning to Earth? (g = 9.81 m/s2)

*asked on October 6, 2013* -
## Math(problem solving)

Four darts are thrown at this dartboard. If all four darts hit the board, how many different point totals are possible? there are 4 circles with point totals: working out from the middle bulls eye.. bulls eye = 9 2nd circle = 7 3rd circle = 4 outter circle

*asked on March 6, 2013* -
## microeconomics

1. Market demand is given as QD = 250 – 0.5P. Market supply is given as QS = 2P. In a perfectly competitive equilibrium, what will be the value of consumer surplus? a.$10 000 b.$20 000 c.$40 000 d.$80 000 2. Market demand is given as QD = 250 – 0.5P.

*asked on February 13, 2013* -
## chemistry

Calculate the concentration of oxalate ion (C2O42−) in a 0.175 M solution of oxalic acid (C2H2O4). [For oxalic acid, Ka1 = 6.5 × 10−2, Ka2 = 6.1 × 10-5.]

*asked on February 22, 2011* -
## Physics (Mathmate)

When a force is applied to an object with mass equal to the standard kilogram, the acceleration of the mass is 3.25 m/s2. When the same magnitude force is applied to another object, the acceleration is 2.75 m/s2. What is the mass of the object? What would

*asked on June 15, 2010* -
## Economics

advantages and disadvantages of allocating resources through the public sector

*asked on January 30, 2010*