# laura

Popular questions and responses by laura-
## math

One day is 86,400 seconds. Express this number in scientific notation and estimate how far the sun's light travels i a day.

*asked on December 7, 2011* -
## Chemistry

Which of the following pairs would make a good buffer? A. H2C2O4 and HC2O4- B. HNO3 and NO3- C. NaOH and NaCl D. HCl and NaOH Would it be C? I think I remember learning about these in a lesson about buffers, hence why my instinct is to go with C...

*asked on September 17, 2016* -
## math

A group of people were asked if they had run a red light in the last year. 433 responded "yes", and 424 responded "no". Find the probability that if a person is chosen at random, they have run a red light in the last year.

*asked on November 15, 2016* -
## science- physics

A car is traveling at a steady 90 km/h in a 50 km/h zone. A police motorcycle takes off at the instant the car passes it, accelerating at a steady 7.3 m/s/s.How much time elapses before the motorcycle is moving as fast as the car? How far is the motorcycle

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

At a certain temperature, 0.900 mol of SO3 is placed in a 2.00-L container. 2SO3(g) 2SO2(g)+O2(g) At equilibrium, 0.130 mol of O2 is present. Calculate Kc. Kc= ? Please post the answer if possible or the steps in detail; I have attempted this problem many

*asked on March 8, 2013* -
## physics

A space station, in the form of a wheel 110 m in diameter, rotates to provide an "artificial gravity" of 3.00 m/s2 for persons who walk around on the inner wall of the outer rim. Find the rate of rotation of the wheel (in revolutions per minute) that will

*asked on July 10, 2010* -
## Math

The cost (in dollars) of producing x air conditioners is C=g(x)=560+40x. Find a formula for the inverse function g−1(C).

*asked on September 19, 2016* -
## Physics

A tow truck pulls a car from rest onto a level road. The tow truck exerts a horizontal force of 1500 N on the car. The frictional force on the car is 810 N. Calculate the work done by each of the following forces on the car as the car moves forward 12 m:

*asked on May 1, 2017* -
## Chem 110

supposed that a liter of sample water contains 1.00 mmol of Ca2+ ions and 1.50 mmol HCO3- ions. how many millimoles of CaCO3 will precipitate if this water is boiled for 15 mins?

*asked on May 9, 2013* -
## Principles of Finance HELP!!!

Problem 16-7. Pro forma income statement At the end of last year, Roberts Inc. reported the following income statement (in millions of dollars): Sales 3000 Operating costs excluding depreciation 2450 EBITDA 550 Depreciation 250 EBIT 300 Interest 125 EBT

*asked on September 29, 2006* -
## MATH

a borrower received a 30 year ARM mortgage loan for 200,000. Rate caps are 3/2/6 the start rate is 3.50% AND the loan adjusts every 12 months for the life of the mortgage, The index used for this mortgage is LIBOR which for this exercise is 3% at the start

*asked on May 19, 2018* -
## science- physics

Find the x- and y-components of the vector d⃗ = (6.0 km , 31 ∘ left of +y-axis). I worked it out and got 5.14, 3.09 and apparently it's wrong, I don't know what I did wrong.

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

Hi, I was hoping someone could double check a chemistry answer for me. I am trying to calculate the Ksp of Ag2CrO4. This question is based on a experiment to determine ksp experimentally. In the experiment the Ksp of silver chromate was calculated using a

*asked on May 26, 2013* -
## chemistry

how many "particles in solution" will form from each sucrose (C12H22O11) molecule added to water? Explain. I don't understand where I am supposed to start... What do I need to know to do this problem? thank you

*asked on September 12, 2012* -
## Geometry

line BD bisects angle ABC. Find angle ABD, angle CBD, and angle ABC if angle ABD equals 3x+6 and angle DBC equals 7x-18 please help it would mean a lot

*asked on September 10, 2015* -
## Physics

At the low point in its swing, a pendulum bob with a mass of 0.2 kg has a velocity of 4 m/s What is the Kinetic at the low point? and Ignoring air resistance how high will the bob swing above the low point before reversing direction?

*asked on February 15, 2013* -
## algebra

Chase scored 14 points on Monday, and he doubled his score each day thereafter. How many points did he score on Thursday? A. 224 points B. 112 points C. 56 points D. 42 points Thanks :)

*asked on January 24, 2013* -
## college

Under typical conditions, 1 1/2 ft of snow will melt to 2 in of water. To how many inches of water will 4 1/3 ft of snow melt?

*asked on October 29, 2010* -
## Physics

Assuming 95.0% efficiency for the conversion of electrical power by the motor, what current must the 12.0-V batteries of a 845-kg electric car be able to supply to do the following? (a) accelerate from rest to 25.0 m/s in 1.00 min (b) climb a 200-m high

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

Of the infinitely many lines that are tangent to the curve y = −7 sin x and pass through the origin, there is one that has the largest slope. Use Newton's method to find the slope of that line correct to six decimal places.

*asked on November 20, 2014* -
## algebra

A house has increased in value by 38% since it was purchased. If the current value is $483,000 , what was the value when it was purchased?

*asked on May 4, 2016* -
## Math

Alfonso got an 87.5% on his test. He got 21 right. How many questions were on the test??

*asked on November 28, 2010* -
## Math

A recipe uses 3 cups of flour to 1 1/6 cups of milk. if you have 2 cups of flour how much milk should u use

*asked on July 7, 2019* -
## math (log)

Express as a single logarithm 2log3 + 4log2 I'm confused as to how to do this, I keep getting the wrong answer. Thank you!

*asked on January 29, 2018* -
## stats

The coding department of Community Physician’s Clinic is interested in purchasing a software program that will edit claims before they are sent to the Billing Office. The license fee for the software is $60,000 per year. The software is expected to

*asked on November 8, 2016* -
## Chemistry help please!

Why does a clear, saturated solution of PbI2 form a yellow precipitate when a small amount of KI is added to the solution? A. KI is insoluble in PbI2. B. PbI2 is always insoluble in water. C. Adding KI is like adding I-, which drives the reaction toward

*asked on September 19, 2016* -
## Calculus

An island is 3 mi from the nearest point on a straight shoreline; that point is 6 mi from a power station. A Utility company plans to lay electrical cable underwater from the island to the shore and then underground along the shore to the power

*asked on April 30, 2016* -
## math help please?!

An object moving vertically is at the given heights at the specified times. Find the position equation s = 12 at^2 + v (small o) t + s (small o) for the object. At t = 1 second, s = 161 feet At t = 2 seconds, s = 98 feet At t = 3 seconds, s = 3 feet a.

*asked on August 29, 2016* -
## Chemistry

Acetylene gas, C2H2, reacts with oxygen according to the following equation. If 46.0 g of acetylene reacts with 100.0 g of oxygen, what is the theoretical yield of heat produced from the reaction? ___ C2H2(g) + ___ O2(g) → ___ CO2(g) + ___ H2O(g);

*asked on December 12, 2014* -
## Physics

A moving 3.20 kg block collides with a horizontal spring whose spring constant is 224 N/m. The block compresses the spring a maximum distance of 5.50 cm from its rest position. The coefficient of kinetic friction between the block and the horizontal

*asked on January 1, 2014* -
## I NEED HELP!.. Algebra

Find a solution to the following system of equations. -5x + y = -5 -4x + 2y = 2

*asked on December 21, 2012* -
## Chemistry

Combustion analysis of an unknown compound containing only carbon and hydrogen produced 2.277 g of CO2 and 1.161 g of H2O. What is the empirical formula of the compound? How do I go about solving this?

*asked on September 19, 2010* -
## college math

Prove: 3/ a(2a^2 + 7)

*asked on March 8, 2009* -
## stats

In September, the hospital had three coders who coded 1,500 inpatient records, and 22 of the records failed the quality screens. a. What is the average number of records coded by each coder? b. What was the average number of records coded each working day

*asked on November 8, 2016* -
## math

any sound from one focus of an ellipse reflects off the ellipse directly back to the other focus. This property explains whispering galleries such as Statuary Hall in Washington DC. Imagine a whispering gallery in the shape of a semi-ellipse. The distance

*asked on August 29, 2016* -
## math

find the standard form of the complex number shown below 9(cos 11pi/6 + isin 11pi/6) a. 2/9 - 2(squareroot)3/9 i b. -4(squareroot)3/9 + 4/9 i c. 9/2 - 9(squareroot)3/2 i d. 9(squareroot)3/2 - 9/2 i e. -9(squareroot)3/4 - 9/4 i

*asked on July 16, 2016* -
## Chemistry

A spoon of sterling silver is 92.5% silver by mass and the rest is made of other metals, usually copper. If the spoon contains 0.557 mol of silver, what is the mass of the spoon?

*asked on December 12, 2014* -
## Physics

Which of the following best describes the image from a thin convex lens that forms whenever the object is at a distance more than two focal lengths from the lens?

*asked on November 14, 2010* -
## Physics

A bike is travelling at a velocity of 7 m/s. The cyclist brakes for 2 seconds when a dog runs out in front of her. The bikes new velocity is 4m/s. Calculate the acceleration of the bike

*asked on May 13, 2020* -
## Math (pre-calc)

log2(log4x) = 1 Solve the equation The bases are 2 and 4 respectively, I'm just not sure how to signify that on the keyboard. Thank you so much, help is really appreciated.

*asked on January 25, 2018* -
## English II

Read the following poem and answer the question that follows. "I Like to See it Lap the Miles" by Emily Dickinson I like to see it lap the miles, And lick the valleys up, And stop to feed itself at tanks; And then, prodigious, step Around a pile of

*asked on November 12, 2013* -
## Grammar

Read the following short excerpt of student writing. Use your vocabulary and grammar knowledge to determine which suggestions you would make to improve his or her grammar and word choice. I really thought she loved me but I discovered her grave betrayal

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

A cell phone company’s profit is modeled by the function p(x) = 10x − x2 − 1, where p is expressed in thousands of dollars and x is the number of phones sold in hundreds. How many phones must the company sell to make a profit of more than $15,000?

*asked on April 13, 2012* -
## chem sorry the last one did not have the question

A sample of PCl5 weighing 2.69 grams is placed in a 1.000 liter flask and vaporized completely at 250 o C. The final pressure observed at this temperature is 1.000 atmospheres. Note that some, but not all of the PCl5 decomposes according to the equation:

*asked on December 6, 2011* -
## Physics

Calculate the hang time of an athlete who jumps a vertical distance of 0.75 meter.

*asked on November 25, 2010* -
## math

A cereal company finds that the number of people who will buy one of its products in the first month that it is introduced is linearly related to the amount of money it spends on advertising. If it spends $40,000 on advertising then 100,000 boxes of cereal

*asked on February 18, 2010* -
## college math

when eggs in a basket are removed 2,3,4,5,6 at a time there remain, respectively, 1,2,3,4,5 eggs. when they are taken out 7 at a time, none are left over. find the smallest # of eggs that could have been contained in the basket.

*asked on April 19, 2009* -
## math

A dealer offers a computer software program whose list price is $500 at a 19% discount. She will give an extra 3% discount if paid in cash. What is the selling price if payment is made in cash? If 500=81%, _____=78% (this comes from subtracting 19% from

*asked on December 16, 2008* -
## physics

a roller coaster car moves 200 ft horizontally and then rises 135 ft at an angle of 30 degrees above the horizontal. It then travels 135 ft at an angle of 40 degrees downward. what is its displacement from its starting point? im not really sure what to do,

*asked on September 2, 2008* -
## chemistry

Calculate the Ka of nitrous acid if a 0.200 mol/L solution at equilibrium at SATP has a percent ionization of 5.8%

*asked on April 5, 2008* -
## math algebra

the product of two consecutive even numbers is 440. What is the sum of the numbers?

*asked on November 30, 2016* -
## Chemistry

Given the reaction: Cu2+(aq) + S2-(aq) CuS(s) What will happen (a) if CuSO4(aq) is added? And (b) if Na2SO4(aq) is added? A. (a) Nothing; (b) Less product will form B. (a) Less product will form; (b) Nothing C. (a) Nothing; (b) More product will form D.

*asked on September 18, 2016* -
## Physics

At a constant velocity, a 5kg bag of cement is pulled straight up a 7m wall. How much work is done by the puller? (Gravitational pull is 9.8m/s2, W(J)=F(N)*D(m) How do I work this problem??

*asked on May 23, 2015* -
## Chemistry

If NaCl has a solubility of 36.0 g in 100 g of H2O at 20 °C, how many moles of water are needed to prepare a saturated solution containing 0.263 mol of NaCl at 20 °C?

*asked on December 12, 2014* -
## Analytical Chemistry

Match the following terms about analytical precipitations to their definitions: A.) Coprecipitation B.) Adsorption C.) Absorption D.) Gathering E.) Masking F.) Digestion G.) Peptization 1.) Inclusion or occlusion of impurities within a crystal. 2.) Binding

*asked on February 28, 2014* -
## English II

Which of these sentences contains an oxymoron? A. Mr. Keynes was a workaholic who found vacations to be about as relaxing as six rounds wrestling with an alligator. B. Despite his desire to travel during his week off, Mr. Keynes was unable to think of any

*asked on November 7, 2013* -
## World History

What impact did Emperor Constantine's establishment of the “New Rome” (Constantinople) have on the Roman Empire? A.The expense of building the new city impoverished the later Empire. B. The pope moved his headquarters from “Old Rome” to “New

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

Solve the system of equations using substitution. y = x + 6 y = –2x – 3

*asked on December 21, 2012* -
## algebra

Solve the system of equations using substitution. y = 2x – 10 y = 4x – 8

*asked on December 21, 2012* -
## Physics

A person climbs from a Paris metro station to the street level by walking up a stalled escalator in 96.5 s. It takes 60.0 s to ride the same distance when standing on the escalator when it is operating normally. How long would it take for him to climb from

*asked on September 21, 2012* -
## Math- Trigonometry

The point, in on the terminal side of an angle in standard position find the exact value of the six trigonometric functions of the angle a. (8,15) b.(-9,-40)

*asked on May 20, 2012* -
## physics

Two trains face each other on adjacent tracks. They are initially at rest, and their front ends are 50 m apart. The train on the left accelerates rightward at 1.05 m/s2. The train on the right accelerates leftward at 0.93 m/s2. (a) How far does the train

*asked on August 17, 2011* -
## prescriptivists

which statement does NOT describe prescriptivists? A} language should be rocorded, not judged. B} language use should follow strict rules. C} language use should never change. D} language use should be judged and evaluted. .The answer i choose is C.

*asked on February 8, 2010* -
## algebra

The sides of a triangle are in the ratio 5:12:13. What is the length of each side of the triangle if the perimeter of the triangle is 15 in?

*asked on August 18, 2009* -
## Chemistry

Give an example of a disaccharide

*asked on February 22, 2009* -
## statistics

The J.R. Simplot Company produces frozen French fries that are then sold to customers such as McDonald's. The "prime" line of fries has an average length of 6.00 inches with a standard deviation of0.50 inch. To make sure that Simplot continues to meet the

*asked on May 1, 2018* -
## math (trigonometry)

A ferris wheel has a diameter of 100m and the bottom of the wheel is 4m above the ground. It rotates two times every 10 minutes. Using this information, complete each question. c) Determine the angular velocity of the Ferris wheel in radians/second d)How

*asked on January 27, 2018* -
## pre calc

Find the point of intersection of the pair of straight lines. y = −5x − 4 −y = 6x + 3

*asked on January 5, 2017* -
## Chemistry

When are more products of a reaction available initially than at equilibrium? A. K = 0 B. Q < K C. Q = K D. Q > K

*asked on September 17, 2016* -
## (MCV4U) Vectors

The air velocity of helicopter Hal is 200km/h due west. Hal's ground velocity is 180km/h in the direction N80*W. Determine the wind velocity. Please help! I know i should be drawing a diagram but I am very confused with how to do this question! Thank you!

*asked on October 3, 2014* -
## World History

Which remained strongly organized and grew more powerful as the Western Roman Empire collapsed? the military command the Christian Church the Orthodox Church the trade networks

*asked on November 26, 2013* -
## English (PLEASE I NEED HELP)

Read the following short excerpt of student writing. Use your vocabulary and grammar knowledge to determine which suggestions you would make to improve his or her grammar and word choice. I really thought she loved me but I discovered her grave betrayal

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

Phosphoric acid is a triprotic acid with the following pKa values: pKa1=2.148 pKa2=7.198 pKa3=12.375 You wish to prepare 1.000 L of a 0.0200 M phosphate buffer at pH 7.11. To do this, you choose to use mix the two salt forms involved in the second

*asked on March 28, 2013* -
## physicis

a 0.30 kg mass attached to a spring is pulled back horizontally across a table so that the potential energy of the system is increased from zero to 120 J. Ignoring friction what is the kinetic energy of the system after the mass is released and has moved

*asked on February 15, 2013* -
## algebra URGENT!

Solve the system using elimination. 2x – 2y = –8 x + 2y = –1 And this one: Solve the system using elimination. 3x – y = 28 3x + y = 14 Pleease help me :(

*asked on December 21, 2012* -
## algebra

The sum of two numbers is 82. Their difference is 24. Choose the system of equations that describes this situation. Solve by elimination to find the two numbers.

*asked on December 21, 2012* -
## algebra

Which graph represents the following system of equations? y = 3x + 3 y = –x – 3

*asked on December 21, 2012* -
## chem

A sample of PCl5 weighing 2.69 grams is placed in a 1.000 liter flask and vaporized completely at 250 o C. The final pressure observed at this temperature is 1.000 atmospheres. Note that some, but not all of the PCl5 decomposes according to the equation:

*asked on December 6, 2011* -
## chemistry

1 gram of C3H8 gas and 1 gram of O2 gas are delivered to a metal sphere with a fixed volume of 1 L. After the two gases are introduced, the two reactants are ignited and burned according to the balanced reaction: C3H8(g)+5O2(g)changes to 3CO2(g)+4H2O(g)

*asked on December 6, 2011* -
## chemistry

A pressure cooker with a volume of 6 L is filled with 27 grams of water and heated to 390.2 K. What is the pressure (atm) in the cooker?

*asked on December 6, 2011* -
## physics

A passenger train is traveling at 30 m/s when the engineer sees a freight train 357 m ahead of his train traveling in the same direction on the same track. The freight train is moving at a speed of 5.9 m/s. (a) If the reaction time of the engineer is 0.43

*asked on August 18, 2011* -
## physics

A bus accelerates at 1.4 m/s2 from rest for 10 s. It then travels at constant speed for 26 s, after which it slows to a stop with an acceleration of magnitude 1.4 m/s2. (a) What is the total distance that the bus travels? (b) What was its average velocity?

*asked on August 17, 2011* -
## physics

a simple pendulum consists of a bob of mass 1.8 kg attached to a string of length 2.3 m. the pendulum is held at an angle of 30 from the vertical by a light horizontal string attached to a wall, as shown above. calculate the tension in the horizontal

*asked on March 3, 2011* -
## please i need help accounting

i have a promblem it gives me the information and form i understand the information but cant fill out the form because i don't know how and its 71 points out of the whole exam. is there anyway u can help me out if i give you the information. its about

*asked on September 28, 2009* -
## Economics

1. Products that would be used in calculating GDP include: a. Toys manufactured in China at a factory owned by a U.S. company b. cars manufactured in Tennessee at a factory owned by a Japanese automobile company c. plastic manufactured in Kentucky and sold

*asked on February 11, 2009* -
## Pre-algebra 7th NEED HELP

This is a question my teacher gave me and there are no parenthesis or whatever you might think it needs. It's 20 divided by 4 minus 5 plus 12. I think the answer is -12, but I'm not sure. PLEASE HELP!!!

*asked on September 23, 2008* -
## Pre-Algebra 7th

What does 20 divided by 4 minus 5 plus 12 equal? I'm trying to understand the order of operation. I think the answer might be -12. Is this correct?

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

If a seed is planted, it has a 80% chance of growing into a healthy plant. If 11 seeds are planted, what is the probability that exactly 1 doesn't grow?

*asked on March 25, 2020* -
## algebra

1. At a college library exhibition of faculty publications, 3 different mathematics books, 4 different social science books, and 3 different biology books will be displayed on a shelf. In how many ways can these ten books be arranged on the shelf if all

*asked on March 2, 2020* -
## math

Write an expression to represent: The sum of seven and the quotient of a number xxx and eight.

*asked on December 19, 2019* -
## account

The net income of Hendley Company for the year is $25,000. Withdrawals during the year were $30,000. No new capital contributions were made during the year. Which of the following statements is TRUE?

*asked on May 17, 2019* -
## Precalculus

Find the distance that the earth travels in nine days in its path around the sun. Assume that a year has 365 days and that the path of the earth around the sun is a circle of radius 93 million miles. [Note: The path of the earth around the sun is actually

*asked on March 20, 2019* -
## Chemistry

pH indicators change color at their _____. The pH at which the color change happens for a particular indicator molecule depends on its: A. pKa; concentration. B. pKa; Ka or Kb. C. equivalence point; Ka or Kb. D. equivalence point; concentration. Is the

*asked on September 18, 2016* -
## Physics

A cube of side L is place in a uniform electric field E = 3200 N/C. What is the net flux through the cube. Assume the electric field lines are parallel with the edges of the cube. Make sure you know why this is the answer. I know its not perpendicular or

*asked on June 28, 2016* -
## Language A

how does the author of selection 1 express his or her point of view differently than the author of selection two? author of selection one agrees with abandoning federal protection of grizzly bears author of selection one believes that the increase in

*asked on May 19, 2016* -
## geometry

The area of a triangle is 6 square feet. The base is 3 times the height. What is the base of the triangle?

*asked on March 22, 2016* -
## math

Sandy measures the length of a hockey stick. she says it it 4 units long. what unit did she use? A. cubes B. inches C. feet D. yards

*asked on November 4, 2014* -
## math homework help

motorcycle company invested 250,000 at 4.5% compounded monthly to be used for the expansion of their manufacturing facilities how much will available for the project in 3.5 years?

*asked on May 20, 2014* -
## History

How did tea change the life in Europe?

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

Person A walks 6.0 m at an angle of 30 north of east. Person B walks 7.0 m at an angle of 42 west of north. How does the component of the displacement of person A along the north direction compare with the component of the displacement of person B along

*asked on December 6, 2013*