# amy

Newest questions and responses by amy-
## Physics

How do the pressure variations with depth affect our ability to explore the ocean? In particular, what are some of the challenges of scuba diving?

*asked on December 12, 2018* -
## algebra

the green team at middle school wants to beautify the school garden ....the green team is bulding a fence around garden . what is the total amount of fence they wiil need to complete project length 6x+16 . w= 3x+8 other side l . l =4x+10 other side .

*asked on November 17, 2018* -
## Math

First of all, sorry to post a similar question to the one I asked before. I do not know if that is allowed, my apologies. Calculate the sum from k=1 to infinity (or n) of (k^4) - (k-4)^4 The book says that the answer is n^4, but I find this incoherent as

*asked on November 14, 2018* -
## Math

Calculate the sum from k=1 to infinity (or n) of (k^4)- (k-1)^4 It says that the solution is n^4, but I do not know why, I tried separating it in a telescoping sum, and expanding it, but I obtain at the end more values than expected. Please help

*asked on November 14, 2018* -
## Math

Two successive discounts of 50% and 50% are followed by two successive increases of 20% and 20%. What single percentage change would produce the same result?

*asked on November 10, 2018* -
## Math

Jason and his four friends want to rent scooters. Scooters 'R Us rent scooters for a $50 fee plus $12 for each scooter. How much does each friend pay if they rent 5 scooters and they want to split the cost evenly? Write an expression to show the total cost

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

Seawater contains approximately 3.5%NaCl by mass and has a density of 1.02 g/mL. What volume of seawater contains 9.0 g of sodium?

*asked on October 17, 2018* -
## SAT Math

If the expression 4x^2/2x-1 is written in the equivalent form 1/2x-1+A, what is A in terms of x? A) 2x+1 B) 2x-1 C) 4x^2 D) 4x^2-1

*asked on October 9, 2018* -
## Statistics

A breathalyser test is used by police in an area to determine whether a driver has an excess of alcohol in their blood. The device is not totally reliable: 8 % of drivers who have not consumed an excess of alcohol give a reading from the breathalyser as

*asked on October 9, 2018* -
## science

How does crossing-over result in genetic recombination? A-It mixes half the maternal chromosomes with half the paternal chromosomes. B- It randomly separates the maternal and paternal chromosomes. C- It reduces the original cell’s chromosome number by

*asked on October 5, 2018* -
## College Math

A rectangle is three times as long as it is wide. Squares of side 2 feet are cut from each corner. Then the sides are folded up to make an open box. Express the volume of the box as a function of the width, x.

*asked on October 5, 2018* -
## Pre Calculus

Find the number of units that produces maximum revenue given by R = 900x-0.1x^2, where R is the total revenue in dollars and x is the number of units sold.

*asked on October 3, 2018* -
## Math

The graph of f(x)=1/x^2 is horizontally compressed by a factor of 14, then shifted to the right 9 units and up 3 units.

*asked on September 17, 2018* -
## Chemistry

In a butane lighter, 9.8 g of butane combines with 35.1 g of oxygen to form 29.6 g carbon dioxide and how many grams of water?

*asked on September 14, 2018* -
## Chemistry

A sample of aluminum with mass of 53.3 g is initially at 143 ∘C What is the temperature of the aluminum after it loses 2.76 x 103 J?

*asked on September 14, 2018* -
## Chemistry

A 5.0×101 kg sample of water absorbs 333 kJ of heat. If the water was initially at 23.1 ∘C, what is its final temperature?

*asked on September 14, 2018* -
## Science

We know the next following bond energies: C≡O: 1 075 kJ; H−H: 435 kJ; C−H: 393 kJ; C−O: 356 kJ; O−H: 464 kJ. With that, a) Calculate how many kJs of energy are required to break all the simple bonds in 0,2 moles of CH4. b) With the energy bonds,

*asked on September 3, 2018* -
## Math

At Janine's party ,the orchestra has 10 guitar players and 8 flute payers .at jakes party the orchestra has 12 guitar players if the ratio of guitar players to flute players is the same at both parties ,how many flute players are there at jakes

*asked on August 23, 2018* -
## Sat Math

Line l has a y-intercept of 2 and contains the points (a,a) and (2a,12). If a is a positive constant, what is the slope of line l?

*asked on August 12, 2018* -
## Sat Math

0.2B + 0.1S = C Rhia is using the above equation to investigate the carbon footprint, C, in kilograms of carbon dioxide (CO2) emissions, for her morning commute which S miles are by subway and B miles are by bus. How many kilograms of (CO2) per mile does

*asked on August 2, 2018* -
## Sat Math

Gary learned that the value of his car depreciates by 15% per year. Which of the following functions best describes the value of his car the year after the car is worth m dollars? A. f(m) = 0.15m B. f(m) = 0.85m C. f(m) = 1 - 0.15m D. f(m) = 1 - 0.85m

*asked on August 2, 2018* -
## Sat Math

The bottom of a ski slope is 6,500 feet above sea level, the top of the slope is 11,000 feet above sea level, and the slope drops 5 feet vertically for every 12 feet traveled in the horizontal direction. From the top of the slope, Kayla skis at an average

*asked on August 2, 2018* -
## Sat Math

If x is a positive integer and l2x+6l > 10, what is the least possible value of x? NOTE: l2x+6l means absolute value of 2x+6

*asked on August 1, 2018* -
## Sat Math

If y = m^4 = n^3 and y is greater than 1, the mn =? A. y^1/12 B. y^1/7 C. y^7/12 D. y^7

*asked on August 1, 2018* -
## Sat math

Brian and Richard stand back-t0-back. Each boy takes 5 equally spaced steps, in opposite directions from the starting location. At this point, Richard walks to where Brian is in 9 steps. How many times bigger are Richard's steps than Brian's steps? A. 4/5

*asked on July 19, 2018* -
## chem

Pb(aq)2+ + 2e- → Pb(s) Ero = - 0.13 V Sc(aq)3+ + 3e- → Sc(s) Ero = - 2.02 V a) Write a balanced chemical equation for a spontaneous reaction involving these half reactions. b) Explain your rationale for the reaction going in this direction.

*asked on June 14, 2018* -
## History

Which was the leading hydroelectric power producer in 2006?

*asked on May 19, 2018* -
## calc 1

The acceleration function (in m/s2) and the initial velocity v(0) are given for a particle moving along a line. a(t) = 2t + 2, v(0) = −3, 0 ≤ t ≤ 3 (a) Find the velocity at time t. (b) Find the distance traveled during the given time interval.

*asked on May 3, 2018* -
## Physics

In separate experiments, an object is placed 12.0 cm in front of two different mirrors: a flat mirror and a convex mirror. The image formed by the convex mirror is 4.0 cm closer to the mirror than the image formed by the plane mirror. Determine the focal

*asked on April 30, 2018* -
## Physics

When the light of a wavelength 450 nm is passed through a certain diffraction grating, the first order diffraction maximum is found to be at an angle of 35° to the straight through. Calculate the distance between adjacent slits in the grating

*asked on April 28, 2018* -
## Math

Find the consumer surplus at the equilibrium point.(I keep using the formula listed below but get a completely different answer from what the book says. I am a visual person so please show me step by step so I can see where I went wrong. D(x)=(x-6)^2 ; x=3

*asked on April 27, 2018* -
## Calculus 1

y= 3/x^3; [1,3] Find the area under the graph of the function over the integral given. The book answer is 4/3

*asked on April 26, 2018* -
## Physics

The pupil of an eagle’s eye has a diameter of 6.0 mm. Two field mice are separated by 0.010 m. From a distance of 186 m, the eagle sees them as one unresolved object and dives toward them at a speed of 20 m/s. Assume that the eagle’s eye detects light

*asked on April 2, 2018* -
## Physics

A converging lens (f1 = 24.0 cm) is located 56.0 cm to the left of a diverging lens (f2 = -28.0 cm). An object is placed to the left of the converging lens, and the final image produced by the two-lens combination lies 19.7 cm to the left of the diverging

*asked on March 21, 2018* -
## Physics

A converging lens (f1 = 24.0 cm) is located 56.0 cm to the left of a diverging lens (f2 = -28.0 cm). An object is placed to the left of the converging lens, and the final image produced by the two-lens combination lies 19.7 cm to the left of the diverging

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

A filmmaker wants to achieve an interesting visual effect by filming a scene through a converging lens with a focal length of 54.0 m. The lens is placed between the camera and a horse, which canters toward the camera at a constant speed of 7.8 m/s. The

*asked on March 18, 2018* -
## Physics

The frequency of a light wave is the same when the light travels in ethyl alcohol or in carbon disulfide. Find the ratio of the wavelength of the light in ethyl alcohol to that in carbon disulfide. The refractive indices n of carbon disulfide and ethyl

*asked on March 12, 2018* -
## Chemistry 2 - pH

You are given an aqueous salt solution and have determined that its pH is 5.19 at 25°C. Predict which of the following three salt solutions it is most likely to be. solution (1): a solution of ammonium nitrate (NH4NO3) solution (2): a solution of

*asked on February 28, 2018* -
## Physics

A driver in a car traveling at a speed of 56.6 mi/h sees a deer 106 m away on the road. Calculate the magnitude of the acceleration necessary for the car to stop just barely missing the deer (assuming that the deer does not move in the meantime). Answer in

*asked on February 26, 2018* -
## educatial technology

which of the following statements is true of a time management plan? a. it is a work in progress that will need to be altered many times b. the plan you create is the one you should stick with c. you dont need to schedule breaks or free time d. it isnt

*asked on February 24, 2018* -
## Math

The local swimming pool is having a contest and all students are welcome to enter. The pool officials want a new logo that has rotational symmetry with 120⁰ and 240⁰ as its angles of rotation. Draw an entry for the contest.

*asked on February 8, 2018* -
## Pre-Calc

cos^3 = (1/2 cosx)(1+cos2x) Please make the left match the right.

*asked on January 25, 2018* -
## Math

A balloon has a diameter of 10 inches and a height of 20 inches. How much helium will it take to fill the balloon in inches cubed

*asked on January 24, 2018* -
## Physics question

mass 0.3kg is moving on the ground at speed 4m/s towards ball B which is at rest on the ground and has mass of 0.8kg. When A collides with B the ball remains in contact for 0.2 sec after the collision B moves forward with a velocity of 1.8m/s find the

*asked on January 10, 2018* -
## Chemistry

Hi there, can someone please help me with this chemistry problem? Write the equation for the acid-base reaction that takes place when nitric acid (HNO3) dissolves in H2O. (Include the phase of each substance.) I got HNO3(aq) + H2O --> H3O+(aq) + NO3−(aq)

*asked on December 18, 2017* -
## Math

An Anthropologist finds bones that her Instruments measure it as 0.921% of the amount of carbon- 14 the bones would have contained when the person was alive. How long ago did the person die? The half life, t 1/2, carbon 14 is 5,730 years. Round To the

*asked on November 11, 2017* -
## Math

The Mendes family bought a new house 10 years ago for $101,000. The house is now worth $160,000. Assuming a steady rate of growth, what was the yearly rate of appreciation ?

*asked on November 11, 2017* -
## Math

Pedro and Ivan raced each other in a 24-mile bike race. After 2o minutes, Pedro traveled 5 miles. Ivan had spent the 20 minutes travelling at a rate of 16 miles per hour. Which person was in first place after 20 minutes? Use words and/or numbers to show

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

Donald Trump purchased a large box of his own books for $55,000. He gave 25 of the books to other republican nominees and then sold the rest on an Internet website for $63,000, making a profit of $15 on each one. a) How many his books were in the box? b)

*asked on November 8, 2017* -
## Math

Brock Obama, Justin Trudeau and Jinping Xi decide to help Mr Blakely bathe his super cat Mike Wazowski. Brock can bathe Mike Wazowski in x minutes, Justin can bathe it in 2 minutes less than Brock, and Jinping can bathe it in 2 minutes more than Brock.

*asked on November 8, 2017* -
## Math

A game has 30 cards numbered 1 through 30. e cards are shu ed. one card is picked at random. Find each probability. Which cards would give a probability of 1/10 they were picked.

*asked on November 3, 2017* -
## math

3 times a number is greater than half of the number by 50. What is the number?

*asked on October 25, 2017* -
## Genetics

Describe how chromosomes are cultured and prepared for laboratory analysis?

*asked on October 17, 2017* -
## Science

Difference between prokaryotes and eukaryotes

*asked on October 16, 2017* -
## Genetics

Describe how chromosomes are cultured and prepared for laboratory analysis?

*asked on October 15, 2017* -
## Science

Explain water potential and how it affects osmosis?

*asked on October 15, 2017* -
## Genetics

Explain the chromosomal differences between males and females?

*asked on October 14, 2017* -
## Physics

A football player kicks a field goal, launchingthe ball at an angle of 48" above the horizontal. During the kick, the ball is in contact with the player's foot for 0.045 s, and the ball's acceleration is 290 m/sz. Vvhat is the range of the football?

*asked on October 10, 2017* -
## history

In what way does Saudi Arabia play an important role in foreign and security aspects in the Middle East

*asked on October 7, 2017* -
## Social Studies

Why is the legacy of colonial powers a barrier to democracy in the Middle East?

*asked on September 30, 2017* -
## science

Goose grass grows tightly around other plants such as hawthorn bushes. suggest two reasons why this method of growth is an advantage for the goose grass.

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

Let f(x) = x^2 +3x - 1 and g(x) = x^3 +4x^2 +1. Find (f-g)(x) a. (f-g)(x)=-x^3 - 3x^2 +3x b. (f-g)(x)=x^3 - 3x^2 +3x - 2 c. (f-g)(x)=--x^3 - 3x^2 +3x - 2 d. (f-g)(x)=-x^3 - 7x^2 +3x - 2

*asked on September 20, 2017* -
## Lab Math

A stock solution of inulin has a concentration of 500mg/ml. From this stock 0.50ml is diluted with 0.50ml of sterile saline. After 30 min blood is sampled and produces a result of 50ug/ml. What is total extravascular volume?

*asked on September 6, 2017* -
## Math

So I need help with 2 questions. This is what is being asked. Write the slope-intercept forms of the equations of the lines through the given point (a) parallel to the given line and (b) perpendicular to the given line. 1. (3, -2) x - y =0 2. (-4, 1) y + 2

*asked on August 27, 2017* -
## Essay Writing

So I'm supposed to write an essay about promoting South East Asian Literature in general and I don't know how to make a good introduction and how to persuade people in general. Any tips/advice would be great. Thanks :)

*asked on August 10, 2017* -
## math

A fruit seller sold 234 apples.He sold twice as many apples as mangoes.how many more apples did he sell?

*asked on July 13, 2017* -
## Math

A bag of candy contains 11 peppermints, 8 chocolates,13 gumdrops, and 9 licorices. jack randomly takes a gumdrop from the bag and eats it. what is the probability that the next candy she takes will be a gumdrop or a peppermint?

*asked on July 12, 2017* -
## Microbiology

How would you determine the minimum bactericidal concentration of a given microbial agent?

*asked on June 4, 2017* -
## English

Which passage would best reflect Gatsby personality and why ? From the book called Great Gatsby

*asked on May 23, 2017* -
## chemistry

what is something that would lower the freezing point of water to -3.7 degrees c if one mole were placed in 1000 g of water? I don't understand how to do this question, I'd appreciate the help (: Thank you

*asked on May 17, 2017* -
## Physics

A seagull drops a claim from a height of 40m above the rocks. If the air temperature is 0 degrees C, how long after the claim is dropped does the sound of it drinking the rocks directly below reach the seagull? Assume that the seagull hovered in place

*asked on May 15, 2017* -
## physics

a destroyer sends out a sonar pulse that returns from a submarine in 1.68s. if the spped of sound in the sea of water is 1531m/s, how far away is the submarine I don't really understand what the question is asking. I appreciate your help! Thank you

*asked on May 15, 2017* -
## college chemistry!!!

Calculate the pH of 500ml 0.07M nitrous acid solution to which 1.4015 grams of sodium nitrite (KW=68.9953) are added.

*asked on May 12, 2017* -
## chemistry

What is a liquid that is known for its high viscosiy due to H bonds? (not water) I'm not sure how to find this, I feel like it should be easy to just google but I really can't find anything about it. I'd appreciate your help, thank you!

*asked on May 11, 2017* -
## chemistry

So the question I have is: Calculate the pressure of dry hydrogen collected. (Use the water temperature). And the evidence that we obtained was: Length of magnesium 3.8Cm Mass of 1 m of magnesium 1.254g Volume of hydrogen collected 67mL Air temperature 27C

*asked on May 10, 2017* -
## Social studies

1. If a consumer makes monthly payments of $250 to pay off a car loan, what type of credit is she using? (1 point) nonrevolving revolving short term unsecured 2. Caitlin wants to buy an airline ticket, but she’s uncomfortable taking that much cash to

*asked on May 5, 2017* -
## Math

Joe spent .55 of his money in one shop and 2/5 of it in another, he then had €6 left, how much had he at first?

*asked on May 3, 2017* -
## chemistry HELP

a flask containing 50ml of 0.128M sodium acetate is titrated with 0.138M nitric acid. Calculate the initial ph of the acetate solution and calculate the ph after the addition of 24.9ml of nitric acid. pKa for acetate 4.757

*asked on April 27, 2017* -
## physics HELP!!

A diffraction grating has 600 lines/mm. Light with a wavelenght of 600nm is incident on it. A screen is placed 0.1m from the grating. Calculate the distance from the 1st and 2nd order maxima on the screen

*asked on April 26, 2017* -
## physics HELP!!

A capacitor is constructed from two aluminium plates 1.5cm on a side separated by 0.2mm of air. (A) Calculate the capacitance of the capacitor. (2 sig figures) (B)Calculate the voltage required to store 1nJ of energy in the capacitor.

*asked on April 26, 2017* -
## Math

6 times the difference of a number and 9 is 18 less than the number. I need to write out as an equasion. Help!

*asked on April 25, 2017* -
## physics (mirrors)

An object is placed from a concave mirror with a radius of curvature of 50cm. The object has a height of 5cm. a)Calculate the focal lenght of the mirror. b)Calculate the position of the image formed by the mirror. Is the image real or virtual? c)Calculate

*asked on April 25, 2017* -
## physics

1. a) using heat exchange and conservation of thermal energy determine the specific latent heat of fusion for ice. b) determine the percentage error The data we determined was: Hot water: mass - 0.1kg initial temp-87C final temp - 56 C Melted ice: mass -

*asked on April 11, 2017* -
## Physics

Determine the percentage error. So we found that aluminium has a specific heat capacity of 18441J/KgC And I know that the percentage error = mv-av/av x 100% But how do we know the actual value of aluminium? My teacher never gave it to us. And when it says

*asked on April 10, 2017* -
## Physics

Using heat exchange and conservation of thermal energy, determine the specific heat capacity for your metal. So the data we have is: Aluminium: Mass - 0.004 Initial temp - 100C Final temp: 32C Water: Mass -0.1 Initial temp - 20C Final temp - 32C I know

*asked on April 9, 2017* -
## chemistry

So we did an experiment where we mixed Cacl2 and NaCl and then found the mass of the precipitate. Then we compared it to reference data on a standard curve to see the mass of Na2Co3 reacting to produce the CaCo3. So what I'm stuck on is this: Suppose the

*asked on April 4, 2017* -
## algebra 2

how to find the value of sec theta -15/4 and Tan theta 12 when theta is greater than zero and less than 360

*asked on April 2, 2017* -
## chemistry

lactic acid is the avid responsible for the sour test in spit milk. on the basis of combustion analysis, it's percentage composition by mass is 40.00% carbon, 6.71%hydrogen and x% oxygen. a. Calculate the empirical formula of lactic acid b. The molar mass

*asked on March 31, 2017* -
## physics

How long would it take a 750W electric motor to do 1.5x10^5 of work What I have so far: So we know w=!@#$%^&pxd 1.5x10^5=750xd So we can arrange that to find d. And then maybe use a formula to find t? Thank you!!

*asked on March 30, 2017* -
## Physics

Determine the amount of work required for each of the following: a) to lower a 35kg sack of rice through a height of 3.5m b) to carry the 30kg sack of rice 10m along a corridor c)to crave the sack of rice 15m along the corridor at a constant velocity

*asked on March 28, 2017* -
## Physics

A 200h bag of potato chips contains 4.8MJ of energy. How long would it take you working at your maximum body power to consume this energy? So we did 2 trials where we ran up the stairs, and my final power for 1 was 246W and for the other it was 338W. So I

*asked on March 27, 2017* -
## Physics

Hello so my question is an 85kg kangaroo acquires 2.2kJ of energy in jumping straight up and down from rest. How high does the kangaroo jump? My solution: When he's at rest Eg=2200J but in air Eg=0 Eg=mhh 2200=85(9.8)h 2.64m=h Looking at it now it doesn't

*asked on March 27, 2017* -
## math

3 fourth of a class are boys. The girls are 24 less than the boys. How many pupils are in the class?

*asked on March 21, 2017* -
## Maths

Karan took a loan of rs 70000 from a bank. If the rate of interest is 10%per annum find difference in amount he would be paying after 1.5 year if the interest is compound annually and compound half yearly

*asked on March 13, 2017* -
## Math

A taxi service charges a $1.90 fee for each ride plus an additional .80 per mile. If a taxi ride cost $4.30, how many miles did the taxi travel travel during the ride?

*asked on March 8, 2017* -
## Math

A rectangular garden has a length if 6.8 meters and seea perimeter of 20.6 meters. What is the width if the garden?

*asked on March 8, 2017* -
## Math

A carpenter cut pieces from a 12 foot long board that were 4 3/4 feet long and 3 1/2 feet long. What is the length of the remaining part if the board?

*asked on March 8, 2017* -
## Math

Factor the following expression completely: 2ab+6a+12abc

*asked on March 7, 2017* -
## Math

Ziggy earned $7.50 per hour plus an additional $100 in tips in Saturday. He earned more than $145 in all. Write an inequality to show h, the amount of hours he may have worked on Saturday.

*asked on March 7, 2017* -
## Math

A recipe calls for 2 1/4 of salt for every 1 1/8 teaspoon of black pepper. How many teaspoons of salt are needed for each teaspoon of pepper used?

*asked on March 7, 2017*