# john

Popular questions and responses by john-
## Calculus

A stone is dropped from the upper observation deck of a tower, 200 m above the ground. (Assume g = 9.8 m/s^2.) a)Find the distance (in meters) of the stone above ground level at time t. b)With what velocity does it strike the ground? (Round your answer to

*asked on November 13, 2011* -
## Statistics

you roll two fair dice, a green one and a red one? (a) are the outcomes on the dice independent? (b)Find P(1 on green die and 2 on red die) (c)Find P(2 on green die and 1 on red die) (d)Find P(1 on green die and 2 on red die) or (2 on green die and 1 on

*asked on October 30, 2016* -
## English

1. Early in Act II of The Phantom Tollbooth, Milo meets a character named Kakafonous A. Dischord, Doctor of Dissonance. Stage directions tell you that "Two screeches and a bump are heard." The doctor's name and the stage directions are clues to the

*asked on December 3, 2018* -
## calculus

If an arrow is shot upward on Mars with a speed of 52 m/s, its height in meters t seconds later is given by y = 52t − 1.86t2. (Round your answers to two decimal places.) What is the average speed over the given time intervals? (i) [1, 2] (ii) [1, 1.5]

*asked on January 31, 2018* -
## math

In a family with 4 children what is the probability of having 1 boy and then 3 girls, in that order? (Exclude multiple births and assume all outcomes are equally likely). In a family with 4 children, what is the probability of having 1 boy and 3 girls, in

*asked on November 8, 2015* -
## math

Pizzaz pg.103 Did you hear about...

*asked on January 8, 2012* -
## Physics

Question: A Toyota car travelled at the rate of 70 km/hour leaves the house 2 hours after a Kia car has left and overtakes it in 5 hours. at what rate was Kia car travelling? What's the Formula pls? Thanks

*asked on July 21, 2016* -
## physics vectors

Consider the two vectors A with arrow = 3 i − j and B with arrow = − i − 6 j. Calculate the directions of A with arrow + B with arrow and A with arrow − B with arrow. A with arrow + B with arrow ° (counterclockwise from the +x axis) A with arrow

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

A box is given a push so that it slides across the floor. How far will it go, given that the coefficient of kinetic friction is 0.24 and the push imparts an initial speed of 3.8 m/s?

*asked on October 14, 2010* -
## chemistry

1. Calculate the standard enthalpy change for the reaction: C2H4(g) + H2(g) → C2H6(g) given that the enthalpy of combustion for the reactants and products are: ΔHºc(C2H4)(g) = -1411 kJ mol^-1 ΔHºc(C2H6)(g) = -1560 kJ mol^-1 ΔHºc(H2)(g) = -286 kJ

*asked on July 19, 2014* -
## algebra

Cryptic Quiz 1. What do you call a skydiver with the flu? 2. How do you crash a houseboat party?

*asked on May 2, 2013* -
## CHEMISTRY

A Sample of gas originally at 25 degrees C and 1 atm pressure in a 2.5 L container is allowed to expand until the pressure is .85 atm and the temperature is 15 degrees C. What is the final volume of gas? Did anyone get 2.6 L

*asked on May 12, 2012* -
## math

A hacker is trying to guess someone's password. The hacker knows (somehow) that the password is 14 characters long, and that each character is either a lowercase letter, (a, b, c, etc), an uppercase letter (A, B, C, etc) or a numerical digit (0, 1, 2, 3,

*asked on November 8, 2015* -
## Pre-Calc Helppp!!!

Use the Law of Sines to solve for all possible triangles that satisfy the given conditions. (If an answer does not exist, enter DNE. Round your answers to one decimal place. Below, enter your answers so that B1 is smaller than B2.) a = 39, c = 40, angle A

*asked on March 31, 2012* -
## CHEMISTRY

A mixture of Xe, Kr, and Ar has a total pressure of 6.7 atm. What is the mole fraction of Kr if the partial pressures of XE and Ar are 1.6 atm and 2.8 atm? Did anyone get .343 ?

*asked on May 12, 2012* -
## Physics

You toss a tennis ball straight upward. At the moment it leaves your hand it is at a height of 1.5 m above the ground, and it is moving at a speed of 8.0 m/s. (a) How much time does it take for the tennis ball to reach its maximum height? (b) What is the

*asked on September 6, 2014* -
## science

A chair of mass 15.5 is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force = 38.0 that is directed at an angle of 42.0 below the horizontal and the chair slides along the floor.Use Newton's laws to calculate

*asked on August 3, 2012* -
## Calculus

A spinner is used for which it is equally probable that the pointer will land on any one of six regions. Three of the regions are colored red , two are colored green, and one in colored yellow. If the pointer is spun twice, find the probability it will

*asked on December 10, 2007* -
## english

21. identify the appropriate punctuation for the underlined word or phrase In High School, I enjoyed reading (The Catcher in the Rye)

*asked on October 25, 2016* -
## college physics

Superman must stop a 190-km/h train in 180m to keep it from hitting a stalled car on the tracks. part a)If the train's mass is 3.8×10^5kg , how much force must he exert (find the magnitude)? part b)Compare to the weight of the train (give as %). partc)

*asked on April 29, 2012* -
## physics

If a car rolls gently(vo=0) off a vertical cliff, how long does it take to reach 85km/h?

*asked on September 13, 2010* -
## College Math

A block with a mass of m = 31 kg rests on a frictionless surface and is subject to two forces acting on it. The first force is directed in the negative x-direction with a magnitude of F1 = 11 N. The second has a magnitude of F2 = 22.75 N and acts on the

*asked on October 9, 2014* -
## science

Both carbon dioxide and water are pure substances. How are they similar to each other? A. both substances have a set ratio of atoms that cannot be separated by physical means B. both substances have a set ratio of atoms that can be separated by physical

*asked on October 8, 2015* -
## Physics

In uniform circular motion, which of the following quantities are constant: speed, instantaneous velocity, tangential velocity, radial acceleration, tangential acceleration? Which of these quantities are zero throughout the motion?

*asked on October 8, 2013* -
## Chemistry

In a gas mixture of He, Ne, and Ar with a total pressure of 8.40 atm, the mole fraction of Ar is ________ if the partial pressures of He and Ne are 1.50 and 2.00 atm respectively. pHe = 1.50 atm. pNe = 2.00 atm. pAr = 8.40 atm - 1.50 - 2.00 = ?? mole

*asked on January 14, 2007* -
## Science

What is the goal of technology A.to understand the natural world B.to improve how devices operate C.to improve how people live D.to understand how systems operate My answer A

*asked on September 14, 2017* -
## math

Jane is organizing a fundraiser to buy a ping-pong table for the community center. The table costs $500.00. Jane is asking contributors to pay for an equal share of the cost of the table. She already has five contributors lined up. What function models the

*asked on February 7, 2019* -
## Chemistry

I've tried to solve this question multiple ways I just can't seem to get it. I just don't understand what I should be doing. An organic liquid is a mixture of methyl alcohol () and ethyl alcohol (). A 0.220- sample of the liquid is burned in an excess of

*asked on September 16, 2012* -
## Chemistry

Ni2+(aq)+Mg(s)→Ni(s)+Mg2+(aq) Indicate the half-reaction occurring at Anode. Indicate the half-reaction occurring at Cathode.

*asked on May 14, 2014* -
## math

Cyndee wants to invest $50,000. Her financial planner advises her to invest in three types of accounts: one paying 3%, one paying 5 1/2%, and one paying 6% simple interest per year. Cyndee wants to put twice as much in the lowest-yielding, least-risky

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

Homer is giving some cookies to each of his three brothers. To the oldest, he gives half of the cookies and half a cookie. He then gives half of what is now left and half a cookie to his second brother. Finally, he gives half of what is now left and half a

*asked on November 24, 2009* -
## Physics

Bethany, who weighs 420N, lies in a hammock suspended by two ropes tied to two trees. The left rope makes an angle of 45 degrees with the ground, the right one makes an angle of 30 degrees. Find the tension of the left rope. Find the tension of the right

*asked on August 25, 2019* -
## Physics

A police car traveling at 94.5 km/h is traveling west, chasing a motorist traveling at 77.2 km/h. (a) What is the velocity of the motorist relative to the police car? The magnitude and its direction (b) What is the velocity of the police car relative to

*asked on August 1, 2012* -
## physics

A nurse pushes a cart by exerting a force on the handle at a downward angle 35.0º below the horizontal. The loaded cart has a mass of 28.0 kg, and the force of friction is 60.0 N. (a) Draw a free-body diagram for the system of interest. (b) What force

*asked on September 18, 2012* -
## math

Every cereal box has a gift inside, but you cannot tell from the outside what the gift is. The store manager assures you that 16 of the 58 boxes on the shelf have the secret decoder ring. The other 42 boxes on the shelf have a different gift inside. If you

*asked on November 8, 2015* -
## chemistry

what is the mass in grams? a) 3.011 x 10^23 atoms F b)1.50 x 10^23 atoms Mg c)4.50 x 10^12 atoms Cl d)8.42 x 10^18 atoms Br e) 25 atoms w f) 1 atom Au can you please explain a and b to me then i'll come back later and see if i did the rest right? Thanks in

*asked on February 23, 2008* -
## Chemistry

Tarnish on iron is the compound FeO. A tarnished iron plate is placed in an aluminum pan of boiling water. When enough salt is added so that the solution conducts electricity, the tarnish disappears. Imagine that the two halves of this redox reaction were

*asked on May 14, 2014* -
## Data Management

How many different sums of money can be formed from one $2 bill, three $5 bills, two $10 bills, and one $20 bill? the answer at the back of the book is 23, but i don't know how to solve it.

*asked on March 6, 2010* -
## chemistry

In a large building, oil is used in a steam boiler heating system. The combustion of 1.0 lb of oil provides 2.2×107J. Part A How many kilograms of oil are needed to heat 110 kg of water from 24 ∘C to 100∘C? (Assume that 1lb=454g, the specific heat of

*asked on September 23, 2016* -
## atlantic high

Why Was Professor CLabberhead Utterbunk Holding Up a Piece of Bread ?

*asked on April 18, 2009* -
## math

A confectioner has 300 pounds of a chocolate that is 1 part cocoa butter to 7 parts caramel. How much chocolate that is 1 part cocoa butter to 15 parts caramel should be combined with the first in order to create a new chocolate that is 1 part cocoa butter

*asked on March 5, 2016* -
## Calculus

Which of the following integrals correctly computes the volume formed when the region bounded by the curves x^2 + y^2 = 100, x = 6, and y = 0 is rotated around the y-axis? I've narrowed it down to either pi∫(sqrt(100-y^2)-6)^2 dy or

*asked on January 22, 2016* -
## Econ

Suppose the government wants to reduce the total pollution emitted by three firms in its area. Currently, each firm is creating 4 units of pollution in the area, for a total of 12 pollution units. The government wants to reduce total pollution in the area

*asked on May 19, 2012* -
## english

25. which sentence is punctuated correctly? a. "Are you finished yet, Miriam asked?" b. Are you finished yet, " Miriam asked?" c. "Are you finished yet"?Miriam asked. d. "Are you finished yet?" Miriam asked.*** 26. Which sentence correctly uses punctuation

*asked on October 27, 2016* -
## English

Parenthetical expressions include information that may be helpful but are not essential to the meaning of a sentence. They are de-emphasized by ________. A. dashes B. parentheses C. commas D. brackets I'm not really understanding this question. It has to

*asked on February 13, 2015* -
## physics

if two forces 10N and 20N are inclined at angle 60degree to each other. Find the resultant force.

*asked on September 27, 2015* -
## calculus

At noon, ship A is 110 km west of ship B. Ship A is sailing east at 25 km/h and ship B is sailing north at 15 km/h. How fast is the distance between the ships changing at 4:00 PM?

*asked on October 13, 2011* -
## physics

A pelican flying along a horizontal path drops a fish from a height of 5.4m. The fish travels 8.0 m horizontally before it hits the water below. What was the pelican's speed?

*asked on October 25, 2010* -
## Science

A group of parts that work together is called. A. Technology B. Process. C. System. D. Feedback I think its C?

*asked on September 20, 2016* -
## Wave

What feature is NOT defined for a wave pulse? a)period b)wave speed c)the position of a particle at a certain time d)a defined source

*asked on February 8, 2014* -
## Finance

Antiques ‘R’ Us is a mature manufacturing firm. The company just paid a dividend of $11.45, but management expects to reduce the payout by 4.5 percent per year, indefinitely. Required: If you require a return of 11 percent return on this stock, what

*asked on March 11, 2015* -
## Physics

In Figure 9-61, block 1 (mass 2.0 kg) is moving rightward at 8 m/s and block 2 (mass 4.8 kg) is moving rightward at 2.8 m/s. The surface is frictionless, and a spring with spring constant of 1180 N/m is fixed to block 2. When the blocks collide, the

*asked on December 10, 2012* -
## physics

in the hydraulic machine shown, you observe that when the small piston is pulled down 10cm, yhe large piston is raised 1 cm. if the small piston is pushed down with a force of 100n, what is the most weight that the large piston can support?

*asked on January 26, 2012* -
## chemistry

Calculate the standard cell potential for each of the electrochemical cells? 2Ag+(aq)+Pb(s)→2Ag(s)+Pb2+(aq) E∘cell......V? 2ClO2(g)+2I−(aq)→2ClO−2(aq)+I2(s) E∘cell......V? O2(g)+4H+(aq)+2Zn(s)→2H2O(l)+2Zn2+(aq) E∘cell......V?

*asked on April 11, 2014* -
## Physics

An ice cube is placed in a microwave oven. Suppose the oven delivers 105 W of power to the ice cube and that it takes 32,200 J to melt it. How long does it take for the ice cube to melt?

*asked on March 16, 2010* -
## Pre-Calc

A hot-air balloon is floating above a straight road. To estimate their height above the ground, the balloonists simultaneously measure the angle of depression to two consecutive mileposts on the road on the same side of the balloon. The angles of

*asked on March 23, 2012* -
## math

Points $D$, $E$, and $F$ are the midpoints of sides $\overline{BC}$, $\overline{CA}$, and $\overline{AB}$, respectively, of $\triangle ABC$. Points $X$, $Y$, and $Z$ are the midpoints of $\overline{EF}$, $\overline{FD}$, and $\overline{DE}$, respectively.

*asked on March 3, 2015* -
## chemistry

Treatment of gold metal with BrF3 and KF produces Br2 and KAuF4, a salt of gold. Find the mass of the gold salt that forms when a 73.0 -g mixture of equal masses of all three reactants is prepared.

*asked on November 2, 2010* -
## physics

A tennis ball with a speed of 12.5 m/s is moving perpendicular to a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 11.4 m/s. If the ball is in contact with the wall for 0.0139 s, what is the average acceleration

*asked on May 20, 2013* -
## Science

How do global positioning systems use elevation points on Earths system to find latitude and longitude A. By using signals from a network of satellite B. By using topographic maps C. By using satellite images D. By using photography

*asked on May 19, 2017* -
## Statistics

If my p-value = .322 and my significant level is .05 , then My Null Hypothesis is rejected and I must accept the Alternative hypothesis My Null Hypothesis is not rejected My Alternative hypothesis becomes the new Null Hypothesis I cannot make a decision

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

Calculate ΔG∘ at 298 K for the following reactions. Ca(s)+CO2(g)+12O2(g)→CaCO3(s) 2KClO3(s)→2KCl(s)+3O2(g) CO(g)+H2O(g)→H2(g)+CO2(g)

*asked on May 18, 2014* -
## physics 1

In coming to a stop a car leaves skid marks 92m long on the highway. Assuming a decceleration of 7.00m/s^2, estimate the speed of the car just before braking.

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

Our sun rotates in a circular orbit about the center of the Milky Way galaxy. The radius of the orbit is 2.2 1020 m, and the angular speed of the sun is 1.2 10-15 rad/s. (a) What is the tangential speed of the sun? m/s (b) How long (in years) does it take

*asked on March 6, 2008* -
## clemson

A farmer wants to make three identical rectangular enclosures along a straight river, as in the diagram shown below. If he has 1680 yards of fence, and if the sides along the river need no fence, what should be the dimensions of each enclosure if the total

*asked on October 6, 2014* -
## Physics

A small disk of radius R1 is mounted coaxially with a larger disk of radius R2. The disks are securely fastened to each other and the combination is free to rotate on a fixed axle that is perpendicular to a horizontal frictionless table top. The rotational

*asked on December 2, 2011* -
## chemistry

Given overall reaction: P4 + 10Cl2 ---> 4PCl5 Delta H for the reaction = ? PCl5 -----> PCl3 + Cl2 Delta H = +157 kJ P4 + 6Cl2 ----> 4PCl3 Delta H = -1207 kJ Calculate the Delta H for the overall reaction.

*asked on March 31, 2016* -
## Physics

A truck driver slams on the brakes and skids to a stop through a displacement of delta x. (a) IF the truck has twice the mass, by what factor does the stopping distance change? 1) 0.25 or 2) 1 or 3) 4 (b) If the initial velocity of the truck were halved,

*asked on February 25, 2008* -
## Calculus

Find the number a such that the line x = a divides the region bounded by the curves x = y^2 − 1 and the y-axis into 2 regions with equal area. Give your answer correct to 3 decimal places.

*asked on January 22, 2016* -
## Calculus

For a cylinder with a surface area of 90, what is the maximum volume that it can have? Round your answer to the nearest 4 decimal places. The volume of a cylinder is πr^2*h and the surface area is 2πrh+2πr^2.

*asked on November 4, 2015* -
## chemistry

Determine the percentage composition of each of the following compounds a) NaCl b) AgNO3 c) Mg(OH)2

*asked on March 13, 2008* -
## Computers

The Command Prompt found on Windows 10 is very similar to the interface of what past operating system?

*asked on March 21, 2019* -
## World history

Which temporary solution was adopted in 1924 to address the economic problems caused by Germany's inability to make reparations? A-Versailles plan B-Marshall plan C-Dawes plan D-young plan B?

*asked on July 13, 2018* -
## physic

A long straight horizontal wire carries a current = 3.90 A to the left. A positive 1.00 C charge moves to the right at a distance 1.50 m above the wire at constant speed v = 5000 m/s. What is the magnitude of the magnetic field at the location of the

*asked on March 8, 2012* -
## science

How many kilograms of NH3 are needed to produce 1.00 x 10^5 kg of (NH4)2SO4?

*asked on May 23, 2012* -
## Physics

An elevator in a tall building is allowed to reach a maximum speed of 3.3 m/s going down. What must the tension be in the cable to stop this elevator over a distance of 3.4 m if the elevator has a mass of 1330 kg including occupants?

*asked on October 14, 2010* -
## chemistry

Some distilled water is added to an empty beaker. A gram of copper(II) nitrate is added to the beaker with stirring. After a few minutes, what is in the beaker? a. solid copper(II) nitrate and water b. nitrogen gas, copper atoms, electrons, and water c. a

*asked on January 28, 2011* -
## Statistics

Suppose a certain species bird has an average weight of xbar 3.40 grams. Based on previous studies, we can assume that the weights of these birds have a normal distribution with sigma 0.29 grams. Find the sample size necessary for a 98% confidence level

*asked on July 16, 2010* -
## Chemistry

Calculate the pH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

*asked on November 17, 2012* -
## Statistic

A recent poll conducted by Gallup Inc. asked the following question: In general, how much trust and confidence to you have in the mass media - such as newspapers, TV, and radio - when it comes to reporting the news fully, accurately, and fairly? A great

*asked on September 26, 2016* -
## math

Calculate the finance charge and new balance using the previous balance method. Previous balance = $179.32 Annual rate = 16% Finance charge = New purchases = $117.42 Payments/credits = $85.00 New balance =

*asked on June 14, 2010* -
## Fraction

A girl spends 1/4 of her pocket money on monday and 3/8 on wednesday. What fraction of her money is left

*asked on November 3, 2014* -
## Math

(8.86 + 1.0 * 10^-3) / (3.610 * 10^-3) Calculate the above formula, expressing the answer in scientific notation with the correct number of significant figures: 8.86 + 1.0 * 10^-3 = 8.86 + 0.0010 = 8.8610 = 8.86. 8.86/(3.610 * 10^-3) = 2454 2.454 * 10^3

*asked on January 9, 2015* -
## Calculus

Sorry this is really long. Just wondering how I would do each of these A particle is moving with velocity v(t) = t^2 – 9t + 18 with distance, s measured in meters, left or right of zero, and t measured in seconds, with t between 0 and 8 seconds

*asked on February 14, 2016* -
## algebra

in a relationship between variables, what is the variable called that changes in response to another variable? a. function b. input function c. independent variable d. dependent variable

*asked on November 9, 2017* -
## Calculus

dy/dx=x/(x-4) I.will have a slope field with negative slopes in quadrant I II.will have a slope field with positive slopes in all quadrants III.will produce a slope field with columns of parallel tangents

*asked on February 18, 2016* -
## another question algebra

write an explicit formula for the sequence 7,2,-3,-8,-13 then find a14

*asked on June 9, 2008* -
## Chemistry

Explain the production of an emission spectrum in terms of the energy states of an electron. what does that mean someone help me please.

*asked on November 6, 2007* -
## physics

As a protest against the umpire’s calls, a baseball pitcher throws a ball straight up into the air at a speed of 20.4 m/s. In the process, he moves his hand through a distance of 1.57 m. The acceleration of gravity is 9.8 m/s 2 . If the ball has a mass

*asked on February 15, 2015* -
## Chemistry

Which of the following metals or nonmetals are expected to displace Mn or Cl (respectively) from MnCl2? 1. Ca should displace Mn. 2. Br should displace Cl. 3. Cu should displace Mn. 4. I should displace Cl.

*asked on September 22, 2013* -
## physics

racing on a flat track, a car going 32 m/s rounds a curve 56m in radius. what is the car's centripetal acceleration?

*asked on December 1, 2010* -
## Physics

A light beam strikes a piece of glass at a 60.00° incident angle. The beam contains two wavelengths, 450.0 nm and 700.1 nm, for which the index of refraction of the glass is 1.4824 and 1.4750, respectively. What is the angle between the two refracted

*asked on March 15, 2010* -
## chemistry proofread

write the chemical equations for the following sentences a) Aluminum reacts with oxygen to produce aluminum oxide I put Al + O2 ----------> 2Al2O3 b) Phosphoric acid, H3PO4, is produced through the reaction between tetraphosphorous decoxide and water I put

*asked on March 26, 2008* -
## calculus

No idea where to start The cost in dollars of producing x units of a particular camera is C(x) = x2 - 10000. (10 points) Find the average rate of change of C with respect to x when the production level is changed from x = 100 to x = 101. Include units in

*asked on December 16, 2014* -
## chemistry h/w help

The concentration of lead nitrate (Pb(NO3 )2 ) in a 0.726 M solution is __________ molal. The density of the solution is 1.202 g/mL.

*asked on September 15, 2010* -
## Chemistry

Calculate the percent ionization of 0.140 M lactic acid in a solution containing 8.5×10−3 M sodium lactate.

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

If a copper sample containing some zinc impurity is to be purified by electrolysis, the anode and the cathode must be which of the following? a. anode: pure copper cathode: pure zinc b. anode: pure zinc cathode: pure copper c. anode: pure copper cathode:

*asked on April 14, 2008* -
## Chemistry

Naphthalene combustion can be used to calibrate the heat capacity of a bomb calorimeter. The heat of combustion of naphthalene is -40.1 kJ/g. When 0.8210 g of naphthalene was burned in a calorimeter containing 1,000. g of water, a temperature rise of

*asked on February 11, 2013* -
## Math

Let f(x) be a polynomial such that f(cos theta) = cos(4 theta) for all theta. Find f(x). (This is essentially the same as finding cos(4 theta) in terms of cos theta; we structure the problem this way so that you can answer as a polynomial. Be sure to write

*asked on February 8, 2014* -
## math

7. The tennis team is selling key chains as a fundraiser. If its goal is to raise is at least 180, how many key chains must it sell at $2.25 each to meet that goal? Write and solve an inequality. a. 2.25k (greater than or equal to) 180; k (greater than or

*asked on October 18, 2016*