Sunday

April 26, 2015

April 26, 2015

Total # Posts: 712

**Physics**

A centrifuge is a device in which a small container of material is rotated at a high speed on a circular path. Such a device is used in medical laboratories, for instance, to cause the more dense red blood cells to settle through the less dense blood serum and collect at the ...
*October 3, 2013*

**chemistry**

Calculate the number of hydrogen molecules formed when 5.6 mL of ammonia at STP is decomposed by the following reaction: ___NH3 „³ ___ N2 + ___ H2
*September 25, 2013*

**chemistry**

Calculate the volume of oxygen at STP required to burn 3.7 kg C3H6O2 producing CO2 & H2O:
*September 25, 2013*

**SAT prep math **

Maria has two piggy banks. In one piggy bank she saves dimes and in the other she saves nickels. At the end of each month she saves 40 nickels and 30 dimes
*September 18, 2013*

**Physical Science**

a student is given a 10 gram sample of gold that has a density of 19.32g/cm3. The student is then given a 5 gram sample of an unknown substance and told the density of the unknown substance is 19.32g/cm3. What is the unknown substance
*September 10, 2013*

**chemistry**

determine the mass of CO2 produced when 51.2 g of CaO is reacted with 50.0 g of C according to the unbalanced equation CaO + C --------CaC2 =CO2
*August 26, 2013*

**chemistry**

in the reaction of magnesium metal with hydrochloric acid to produce magnesium chloride and hydrogen gas. If 4.59 mol of magnesium and 4.59 mol of hydrochloric acid are reacted, how many moles of magnesium chloride are produced ?
*August 26, 2013*

**Please Help with calculus**

How to evaluate x=0 and dx=-.03? I got(1/9)e^(x/9)dx as dy of e^(x/9)and I don't know how I should plug them in.
*June 26, 2013*

**Calculus**

Let y=e^(x/9). a) Find the differential dy. dy = b) Evaluate dy if x=0 and dx=−0.03. dy =
*June 26, 2013*

**Calculus**

Find the linear approximation L(x) of ln(x) at the point a = 12.
*June 25, 2013*

**Calculus**

Find the equation of the tangent line to the curve (piriform) y^2=x^3(4−x) at the point (2,16−−ã). a. Find dy/dx at x=2. dy/dx= b. Write the equation of the tangent line to the curve.
*June 25, 2013*

**Calculus**

Find the linear approximation L(x) of ln(x)at the point a = 12.
*June 20, 2013*

**Calculus**

The radius of a circular disk is given as 51 cm with a maximum error of 0.04 cm. Use differentials to estimate the maximum error and percent error in the calculated area of the disk.
*June 19, 2013*

**english **

please answer the last question
*June 11, 2013*

**english**

give two examples in the giant's house for character, theme, plot, style, point of view
*June 11, 2013*

**chemistry**

How much carbon dioxide gas is there in a 34.3 L container at 34.0◦C and 5.49 atm? answer in grams
*June 9, 2013*

**Calculus**

Evaluate the following limit, if it exists: lim h-->0 ((sqrt9+h)-3/(h)
*May 31, 2013*

**Calc**

Oscar Corporation is planning to construct an elliptical gate at its headquarters. The width of the ellipse will be 5 feet across and its maximum height along the center will be 3 feet. The company wants to place two bright spots at the foci of the ellipse. How far from the ...
*May 1, 2013*

**math**

kate cut a pizza into fourths. karl cut a pizza of the same size into sixth. After they each ate some pizza, they had the same fraction of pizzas left. What fraction of each pizza was left?
*April 23, 2013*

**pre calc**

Find all solutions of the equation tan^5 x - 9tan x =0. The answer is Ak\pi where k is any integer, the constant A= ??.
*April 14, 2013*

**math**

Find all solutions of the equation 3sin^2 x -7sin x +2 = 0 in the interval [0,2\pi). The answer is x_1= ? and x_2= ? with x_1<x_2.
*April 14, 2013*

**since and cosine please help me!**

that is not right according the program
*April 14, 2013*

**since and cosine please help me!**

Simplify and write the trigonometric expression in terms of sine and cosine: ((2+tan^2 x)(sec^2 x))-1 = (f(x))^2 f(x)= ???
*April 14, 2013*

**sine and cosine**

Simplify and write the trigonometric expression in terms of sine and cosine: sin x + (cot x)(cos x) = (1/f(x)) f(x)= ?
*April 14, 2013*

**cosine and sine HELP!**

Simplify and write the trigonometric expression in terms of sine and cosine: ((2+tan^2 x)(sec^2 x))-1 = (f(x))^2 f(x)= ???
*April 14, 2013*

**math**

Simplify and write the trigonometric expression in terms of sine and cosine: sin x + (cot x)(cos x) = (1/f(x)) f(x)= ?
*April 14, 2013*

**chemistry**

Thimerosal is an organic compound (gram molecular mass = 404.8 g/mol) used to inhibit bacterial growth. A .100%solution of thimerosal is sometimes used as an antiseptic. Assume that this solution has a density of 1.00 g/mL. A. how many grams of thimerosal are found in .500 g ...
*April 7, 2013*

**math**

Simplify and write the trigonometric expression in terms of sine and cosine: sin x +(cot x)(cos x) = 1/f(x) f(x)= ?
*April 7, 2013*

**math**

If tan^2(t) - sin^2(t) = sin^a(t)\cos^b(t), then the positive power a = the positive power b =
*April 7, 2013*

**math**

2a2+5a-25=0
*April 4, 2013*

**phisics**

If You do 100 j of work to elevate a bucket of water,what is its gravitational potential energy relative to its starting position?
*March 14, 2013*

**angles**

A survey team is trying to estimate the height of a mountain above a level plain. From one point on the plain, they observe that the angle of elevation to the top of the mountain is 25 degrees. From a point 1225 feet closer to the mountain along the plain, they find that the ...
*March 10, 2013*

**trig **

The radian measure of an angle of 182 degrees is ?
*March 6, 2013*

**math**

The radian measure of an angle of 182 degrees is
*March 5, 2013*

**Pre calulus only 15 min left HELP!**

((ln(x))^1/2)/(ln(x^1/2))=6 solve for x
*March 3, 2013*

**Physics**

500 calories of heat is added to 2.0 g of water at 80 degrees Celsius. How much steam is produced?
*March 3, 2013*

**math**

write the metric unit of length that is reasonable. a door is about 1 blank wide
*February 25, 2013*

**Math**

The sum of twice a number and another number is 24. The difference of twice the first number and the other number is 12. Which system would model this situation, and what is the solution?
*February 22, 2013*

**math**

what is answer of 7 cubed
*February 19, 2013*

**math**

A certain brand of cereal costs $3.25 per box before sales tax is added. When you buy 5 or more boxes of this cereal you receive 1 additional box for free. What is the average cost per box of cereal for 6 boxes before sales tax are added ? Please helpp
*February 5, 2013*

**English**

What is the significance of the repetition of the word absurd in the play?
*January 22, 2013*

**math**

jeff bought 6 pairs of shoes and 4 jerseys for 560. Jersies cost 1/4 price of one pair of shoes. Find price of shoes and price of jersey
*January 15, 2013*

**Chemistry**

1. Pentane gas (C5H12) combusts with oxygen gas (O2) to form water (H2O) and carbon dioxide (CO2). Write a balanced chemical equation for this reaction and explain the scientific principle (statement) that requires the balancing of an equation to make it conform to reality
*January 15, 2013*

**math**

A group of 132 students chose baseball and soccer as their favorite sports in the ratio of 3:8. How many students chose soccer as their favorite sport?
*January 14, 2013*

**physics**

a mechanic uses a chain and bloc pulley to lift a 875-kg engine 4.0 m to the top of the garage. the downward force on the chain over the 4.0 m distance is 5.0 x 10^4 N. a)calculate the work done in raseing the motor b)how much useful work was done c)what is the inefficiency of...
*January 12, 2013*

**science**

When scientists use one of their five senses to gather information, they are?
*January 8, 2013*

**math**

sam cut a pie into equal slices. there are only 3 slices left. the angle measures for the three slices is 72 degrees. how many slices did sam cut the pie into?
*January 7, 2013*

**math**

At a festival, 2/7 of the number of girls was equal to 3/5 of the number of boys. There were 165 fewer boys than girls. How many children were at the festival in all?
*January 1, 2013*

**math**

Madison spent 5/8 of her savings on a microwave oven & a refrigerator. She used 4/7 of the amount she spent to buy the refrigerator. The refrigerator cost $280 more than the microwave oven. How much savings did Madison start with?
*January 1, 2013*

**Science**

Nevermind, I was looking and I just found the help I needed :)
*December 17, 2012*

**Science**

If you are asked to determine an object’s speed, what information must you have? A.distance and period of time B.distance and change in position C.period of time and direction D.distance and direction
*December 17, 2012*

**Phusics**

Does an object moving in the y direction have KE? If so if you apply a force in the Y direction will the velocity increase?
*December 2, 2012*

**physics**

You have a conversation of EP and with that you have the formula: Mbull*Vi+Mwood*Vi=(Mb+Mw)Vf .o15kg*Vi+15*0=(.015+15)Vf Mult. by 0: .015kg*Vi=(.o15+15)Vf So we can't solve that (i guess we cant curse here) but we move on to where the spring compresses, there is ...
*December 2, 2012*

**physics**

You have a conversation of EP and with that you have the formula: Mbull*Vi+Mwood*Vi=(Mb+Mw)Vf .o15kg*Vi+15*0=(.015+15)Vf Mult. by 0: .015kg*Vi=(.o15+15)Vf So we can't solve that but we move on to where the spring compresses, there is conservation of TME so: 1/2(Mb+Mw)Vf^2...
*December 2, 2012*

**English**

Out side
*November 29, 2012*

**quantitative analysis**

consider a manufacture whose total cost of producing x items is given by c(x) = 10000 + 5x+1/9x^2 a) what is the average cost function of A(x) = c(x)/x? b)how many items should the manufacturer produce in order to minimize average cost? c)what is the smallest average cost? d) ...
*November 27, 2012*

**Stats PLEASE HELP!!!**

Webcredible, a UK-based consulting firm specializ- ing in websites, intranets, mobile devices, and applications, conducted a survey of 1,132 mobile phone users between February and April 2009. The survey found that 52% of mo- bile phone users are now using the mobile Internet...
*November 18, 2012*

**4th grade math**

38700
*November 15, 2012*

**Social Studies**

True
*November 12, 2012*

**Physics**

What is one way in which the magnetic field is similar to the electric field and one way in which the magnetic field is different from the electric field?
*November 7, 2012*

**Chem Lab Help**

Carefully clean and dry a 150 mL beaker, a 250 mL beaker, and a large 155mm test tube. Remove two Alka-Seltzer tablet from their hermetically sealed packet and weight them. Use a clean (use paper towels only, NO water) mortar and pestle to grind the tablets into a fine power. ...
*October 29, 2012*

**Chem Lab Help**

Trial #1 Trial #2 Trial #3 Mass: gelatin capsule (g) .123 .118 .122 Mass: whole alka-seltzer tablet (g) 3.230 3.230 3.230 Mass: capsule + alka-seltzer sample (g) .822 .882 .677 Mass: system before reaction (g) 23.109 23.110 22.735 Mass system after reaction (g) 21.742 21.813 ...
*October 29, 2012*

**CHEMISTRY**

Describe how you would prepare 250. mL of a .500 stock solution of sodium hydroxide. (show all work)
*October 28, 2012*

**Chemistry Lab**

Im not sure how to do these questions though
*October 28, 2012*

**Chemistry Lab**

The experimental data you entered is: Trial #1 Trial #2 Trial #3 Mass: gelatin capsule (g) .123 .118 .122 Mass: whole alka-seltzer tablet (g) 3.230 3.230 3.230 Mass: capsule + alka-seltzer sample (g) .822 .882 .677 Mass: system before reaction (g) 23.109 23.110 22.735 Mass ...
*October 28, 2012*

**Physics**

A photocell shows photoelectric effect when green light shines on it. Which of the following is correct if a green light is replaced by a blue light? Electron emission would get stopped. Electrons are emitted with more velocity. Electrons are emitted with less velocity. ...
*October 25, 2012*

**math**

how to solve identity property,2nd grade
*October 24, 2012*

**Physics**

A photocell shows photoelectric effect when green light shines on it. Which of the following is correct if a green light is replaced by a blue light? Electron emission would get stopped. Electrons are emitted with more velocity. Electrons are emitted with less velocity. ...
*October 24, 2012*

**Physics**

A photocell shows photoelectric effect when green light shines on it. Which of the following is correct if a green light is replaced by a blue light? Electron emission would get stopped. Electrons are emitted with more velocity. Electrons are emitted with less velocity. ...
*October 23, 2012*

**math**

Beth cuts her pizza into thirds, how many pieces did she eat?
*October 18, 2012*

**Math**

How many 2/3 are in 3/4?
*October 15, 2012*

**Algebra**

A scuba diver dives 100 feet below the waters surface. Later she rises 78 feet. How far below the surface is the diver?
*October 13, 2012*

**Algebra 1 **

Ruffles cost $3.49 per bag. Chips-Ahoy cost $3.99 per bag. Bobby spent 42.39. If he bought 5 more bags of Chip-Ahoy than Ruffles, how many bags of each snack did he buy?
*October 11, 2012*

**Physics**

Its postive you dummy
*October 11, 2012*

**Math**

5x6=5x4+5xb
*September 27, 2012*

**7th grade Art**

1.B 2. C 3 A C
*September 26, 2012*

**physics**

1) A boy sledding down a hill accelerates at 1.40 m/s, If he started at rest, in what distance would he reach a speed of 7.00 m/s? 2) An Elevator is moving upward at 1.20 m/s when it experiences an accelerstion of 0.31 m/s downward, over a distance of 0.75m. What will its ...
*September 24, 2012*

**chemistry**

how many grams of NaOH should be used to make 200 mL of a 0.24M solution starting with a .4M HCL solution
*September 22, 2012*

**chemistry**

Assuming that 0.5 grams of a 1.0 gram sample is CaCO3, what should the concentration of HCl(M) be if you want to use 25.0 mL for the titration?
*September 22, 2012*

**Physics**

Thinking Physic-ly: On some toll roads, the ticket is stamped with the time you enter the toll road and the time you exit. How can the toll taker determine if you were speeding?
*September 19, 2012*

**science**

what is the volume of a cabinet 1.20m by 5m by 75cm
*September 18, 2012*

**Calculus**

can you solve it by using separation of differential equations
*September 9, 2012*

**Calculus**

A snowball has a radius of 3 inches. Assume the rate with which the volume of the snowball melts is proportional to its surface area. If, after 1 hour, the radius of the snowball is 2.9 inches, predict what the radius will be after one day. using separation of ordinary ...
*September 9, 2012*

**calculus**

can you solve it with separation of differential equation
*September 9, 2012*

**Economics**

possibly
*September 7, 2012*

**math**

A rectangular slab of concrete is cut from a large block. The slab measures 10.4 inches thick, 1.8 feet long, and 0.0021 miles wide. Find its volume in cubic feet.
*September 6, 2012*

**finite math**

Okay,so: Assume that there are 8 unfilled roles: 3 male and 5 female. There are 5 men and 6 women, including Sally, auditioning for a part in the play. How many of these casts include Sally?
*September 5, 2012*

**social studies**

Is there 51 states? Is DC considered as 5lst or Puerto Rico 51st
*September 3, 2012*

**physics **

Pulling a 1.92 kg. box at a constant speed requires a force of 14.12 N. What is the coefficient of friction (µ) for this box?
*August 24, 2012*

**physics **

A 1.66 kg. load is pulled by a force of 11.03 N. If the coefficient of friction (µk) for this load is 0.602, and the load starts at rest, how long will it take to accelerate the load from rest to a final velocity of 4.90 m/s?
*August 24, 2012*

**physics **

A 3.18 kg. bucket of water is being lowered into a well. It is accelerating downwards at -0.54 m/s2. What is the upwards tension in the rope
*August 24, 2012*

**physics **

A train consists of 40 freight cars, each having a mass of 2.71 × 105 kg. If the engine (which has twice the mass of a freight car) exerts a net force of +1.12 × 105 N, what will be the acceleration of this train?
*August 24, 2012*

**physics **

A bullet is fired through a wall that is 10.0 cm. thick. The bullet entered the wall at 400. m/s, and it exited from the wall at 220. m/s. What was the average acceleration of the bullet while it was passing through the wall?
*August 24, 2012*

**physics **

A ranger in a national park is driving along at 17.9 m/s when a deer jumps into the road 65. m ahead of the vehicle. After a reaction time of t seconds, the ranger applies her brakes, which produce an acceleration of -2.8 m/s2. What is the maximum reaction time she can have if...
*August 21, 2012*

**physics **

While doing some interval training, a runner runs a distance interval at a pace of 4.00 m/s. She then runs the next interval at 4.500 m/s and the last interval at 5.500 m/s. Assuming each interval is exactly 125. m, what is her average speed for this workout?
*August 21, 2012*

**physic**

In order to qualify for the finals in an race, a runner must achieve an average speed of 5.24 m/s for the entire mile race. If she runs at a constant speed of 4.63 m/s for the first half of the 1609 meter race, what constant speed must she maintain for the second half of the ...
*August 21, 2012*

**physics **

Bottled water costs $0.55 for a 0.5 liter bottle. What would it cost to fill a bathtub with bottled water. The bathtub holds 7.13 cubic feet of water. (Recall that 1.00 inch = 2.54 cm, and that a liter is exactly 1000 cm3).
*August 21, 2012*

**AP World History**

What are the limits to studing the interactions across the worlds major water basins?
*August 14, 2012*

**AP World History**

what are the benifits to studing the interactons across the worlds major water basins?
*August 14, 2012*