Sunday

December 4, 2016
Total # Posts: 2,357

**Physics**

Instead of the frictionless wheel in problem 7, imagine that the rope is tied to a frictionless pulley with radius R but an unknown moment of inertia. If the pulley always has half as much kinetic energy as the block, what must be its moment of inertia? The block has a mass m.

*November 17, 2015*

**Calc**

Gravel is being dumped from a conveyor belt at a rate of 20 {\rm ft}^3{\rm /min}. It forms a pile in the shape of a right circular cone whose base diameter and height are always the same. How fast is the height of the pile increasing when the pile is 18 ft high?

*November 16, 2015*

**Math**

Wrong answer

*November 16, 2015*

**Algebra**

Mira’s boat goes 12 mph in still water. It travels 45 miles upstream and back in a total time of 8 hr. What is the speed of the current?

*November 12, 2015*

**Algebra**

The time t required to empty a tank varies inversely as the rate R of pumping.If a pump can empty a tank in 50 min.at a rate of 650 k?L/min, how long will it take the pump to empty the tank at 500kL/min?

*November 12, 2015*

**Algebra**

A 42 ft guy wire reaches from the top of a pole to a point on the ground 15 ft. from the pole. Find how high up the pole does the guy wire reach?

*November 12, 2015*

**Interest**

Find the amount of the annuity if the deposit is $800 quarterly for 6 years at 9% compounded quarterly. Amount=?

*November 10, 2015*

**Compound interest**

The cost of the stereo is 2526.87 i just cant figure out the amount of interest paid, i do I=P*R*T and get 397.87 or something like that and it says its wrong

*November 10, 2015*

**Compound interest**

Stereo Inc. sells a stereo system for $200 down and monthly payments of $70 for the next 3 years. If the interest rate is 5.25% per year, find: a) The cost of the stereo. Answer = $ b) The total amount of interest paid

*November 10, 2015*

**Chem**

Thank you for your help.

*November 2, 2015*

**Chem**

If 0.256 g of a compound containing only carbon and hydrogen atoms is burned efficiently and 0.780 g of carbon dioxide and 0.356 g of water are produced, how many moles of H-atoms are contained in the original (0.256 g) sample?

*November 2, 2015*

**PLEASE HELP MS SUE!!!!!!!!!!!!!!!!!!!!!4**

Its Output cell

*November 2, 2015*

**Chemistry**

Two aqueous solutions, both at 25.00°C (100.0 mL of 0.223 M Pb(NO3)2 and 100.0 mL of 0.144 M Na2S), are mixed together in a calorimeter with a Ccalorimeter of 11.8 J/°C. The temperature of the solution increases by 2.40°C. Assuming that the density and heat ...

*October 28, 2015*

**Computer programming **

I am trying to write a program in C that would be used by a car rental company. This program finds the subtotal, tax amount(6%) and finally the total. The user enters in how many days the car was rented and how many miles were driven. The total is based on this logic. The cars...

*October 27, 2015*

**Math 142 (calculus)**

Determine d^2y/dx^2 for y=(5x^5+7)^4

*October 20, 2015*

**Calculus**

Find c so y=4x+3 is tangent to the curve y=x^2+c

*October 16, 2015*

**Calculus**

An open box with a capacity of 36,000 cubic inches is to be twice as long as it is wide. The material for the box is $.10/sq ft. What are the dimensions of the least expensive box? How much does it cost?

*October 16, 2015*

**Calculus**

An open box is made by cutting squares of side w inches from the four corners of a sheet of cardboard that is 24" x 32" and then folding up the sides. What should w be to maximize volume of the box? I started by trying to get a formula for the volume which I thought ...

*October 16, 2015*

**Chemistry**

@Dr.Bob222 I was answer that answer before but it was wrong

*October 12, 2015*

**Chemistry**

oh Ka is 3.5x10^-4. Sorry about that

*October 12, 2015*

**Chemistry**

What is the pH of a 0.0050 M solution of sodium fluoride? I got 7.58 for pH. Is it correct? but I try to plug in my quadratic formula, I don't get the pH 7.58. I'm really confuse. Please help.

*October 12, 2015*

**Math**

Tell if x and y show direct variation. Explain reasoning. 1) x=2y 2) y-x=6 3) xy=5

*October 7, 2015*

**Physics **

Draw a free body diagram and Apply Newton's 2nd law in both direction. 60 kg chair is pulled along a rough horizontal surface under the action of a 200N force 30 degrees up from horizontal, as shown the acceleration of the chair is 1.5 m/s^2. a) Determine the normal force ...

*October 7, 2015*

**Comma question**

Please use correct place comma for this sentence - Louisa bought mangoes and papayas and oranges.

*October 6, 2015*

**Spanish**

Thank you! that helped a lot!

*September 25, 2015*

**Spanish **

Esta mañana nos (1) _____ temprano en carro sin mapa. Al (2) _____ de la ciudad, Jorge (3) _____ al empleado de una gasolinera dónde (4) _____ el carril para acceder a la autopista. El empleado no (5) _____ contestarle porque no (6) _____ a dónde (7) _____...

*September 25, 2015*

**SPAnish **

Modifique el texto por cambiar los verbos italizados de lo familiar (informal) a lo formal Prepara (1) _____ para salir de viaje el lunes por la mañana. Para ello, haz (2) ______ las maletas, sal (3) _____ de la habitación y métete (4) _____ en el coche. ...

*September 25, 2015*

**probability **

The National Center for Educational Statistics reported that in 2009 the ACT college placement and admission examination were normally distributed and had a mean of 21.1 and standard deviation of 5.1. A college requires applicants to have an ACT score in the top 20% of all ...

*September 21, 2015*

**AP Physics I**

A placekicker is about to kick a field goal. The ball is 26.6 m from the goal post. The ball is kicked with an initial velocity of 19.0 m/s at an angle θ above the ground. Between what two angles, θ1 and θ2, will the ball clear the 2.8-m-high crossbar? (Hint: ...

*September 20, 2015*

**Spanish **

1 of 15 I tried to get there on time, but there was an accident on the freeway: Yo ____(1)____ llegar a tiempo, pero ____(2)____ un accidente en la autopista. Options 1-quise or queria 2-hubo or habia Answers 1- quise 2 -habia 2 of 15 They refused to admit that you already ...

*September 19, 2015*

**probability **

You and your friend just rented a car for an 8,000 mile cross-country road trip. Your rental car may be one of three different types: new (N), nearly one year old (O), and old (L). If the car you receive is brand new, it will break down with probability 0.08. If the car is ...

*September 11, 2015*

**Physics. Help Please**

Gabriele enters an east-w straight bike path at the 3.0-km mark and rides w at a constant speed of 8.0 m/s. At the same time, Xena rides east from the1.0-km mark at a constant speed of 6.0 m/s. 1. Write function x(t) that describe the position of Gabriele as a function of time...

*September 11, 2015*

**probability **

You and your friend just rented a car for an 8,000 mile cross-country road trip. Your rental car may be one of three different types: new (N), nearly one year old (O), and old (L). If the car you receive is brand new, it will break down with probability 0.08. If the car is ...

*September 10, 2015*

**SPANISH **

EL PRETÉRITO. Modifique el párrafo por cambiar los verbos italizados al pretérito. Ejemplo: Tenemos que preguntarle al revisor. Tuvimos que preguntarle al revisor. Voy___(1)___ a coger el tren para irme de vacaciones a la sierra. Ya no me queda___(2)___ ...

*September 10, 2015*

**probability **

You and your friend just rented a car for an 8,000 mile cross-country road trip. Your rental car may be one of three different types: new (N), nearly one year old (O), and old (L). If the car you receive is brand new, it will break down with probability 0.08. If the car is ...

*September 9, 2015*

**math**

An executive drove from home at an average speed of 45 mph to an airport where a helicopter was waiting. The executive boarded the helicopter and flew to the corporate offices at an average speed of 120 mph. The entire distance was 250 miles; the entire trip took three hours. ...

*September 9, 2015*

**math**

The weight of a bag of bricks plus 20% of its weight is 30 pounds. How much does the bag of bricks weigh, in pounds?

*September 9, 2015*

**Stats**

Explain what it means to have a deviation score of -18

*September 8, 2015*

**Statistics**

Assume that the unit of measure for each of the values in the sample is in dollars. What would be the units of measure for the sample: a) mean? b) range? C) Variance? d) Standard deviation?

*September 8, 2015*

**probability **

Alice and Bob each choose at random a number between zero and two. Consider the events events A: The magnitude of the difference of the two numbers is greater than 1/4. Event B: At least one of the numbers is greater than 1/4. Event C: Alice’s number is greater than 1/4. ...

*September 7, 2015*

**probability **

You and your friend just rented a car for an 8,000 mile cross-country road trip. Your rental car may be one of three different types: new (N), nearly one year old (O), and old (L). If the car you receive is brand new, it will break down with probability 0.08. If the car is ...

*September 7, 2015*

**probability **

Anne and Bob each have a deck of playing cards. Each flips over a randomly selected card. Assume that all pairs of cards are equally likely to be drawn. Determine the following probabilities: (1) The probability that at least one card is an ace, (2) the probability that the ...

*September 7, 2015*

**World Geography**

if 1/2 inch equals to ten miles how many inches are there in thirity miles ?

*September 2, 2015*

**Algebra**

Write 3 different algebraic expressions that uses x,y, and z and simplifies to the given value when x=-3, y=-2, and z=-1. The expression should involve only multiplication or division. Values are: 1, -16, and 12.

*September 1, 2015*

**Algebra 2 **

1. A bag contains 12 red checkers and 6 black checkers. You will randomly select two checkers, one at a time, without replacement. (a) In how many ways can you select two checkers so that at least one of the checkers is red? List the ways. (b) What is the probability that you ...

*August 26, 2015*

**math**

A plane is flying at 168 miles per hour with a heading of 43.5° from due north. The wind is blowing a constant 33 miles per hour at 133.5° from due north. Find the ground speed and true course of the plane.

*August 17, 2015*

**science**

i think its A

*August 17, 2015*

**science**

Which of the following chemicals is insoluble in water? A. C6H6 {benzene) B. HCI (hydrochloric acid) C. NH3 (ammonia) D. NaHC03 (sodium bicarbonate)

*August 17, 2015*

**Sophia**

650ft/117.3ft/s=5.5 Is NOT the answer. Nor is 40.6 nor 7.4 nor 8.8 nor 16.2 nor 6.5. Nor is 0! Thinking they didn't stop at all before the crash!

*August 12, 2015*

**Sophia**

Algebra

*August 12, 2015*

**Sophia**

The following formula relates the distance S (in feet) traveled by a vehicle during an emergency stop to the time T (in seconds) it takes to arrive at a complete stop: s(t)=16t^{2} At the scene of an accident, Bill uses skid marks to determine the braking distance of one of ...

*August 12, 2015*

**History**

Ms Sue I am not understanding that is the Maccabean Revolt written for the gentiles to read in the future? Or is it for the Jews so they are aware of the past

*July 19, 2015*

**History**

What was the purpose of account of the Maccabean Revolt? Who was the intended audience?

*July 19, 2015*

**experiment physics**

Stress ke cari jawapan x jumpe

*June 30, 2015*

**Chemistry**

A solution of methanol and water has a vapour pressure of 213 Torr. What would you predict as the mole fractions of each component, assuming ideal behaviour? The vapour pressures of methanol and water are 256 Torr and 55.3 Torr, respectively

*June 4, 2015*

**Chem.**

Thank you

*June 4, 2015*

**Chemistry**

Do you mean 44.8L of Zn?

*June 4, 2015*

**geometry**

what is the surface area of a cube with side of 2 inches? what is the volume?

*May 15, 2015*

**Math**

Find the effective rate of interest (APR) for a loan with a loan amount of $6,300, a time of 270 days, and interest of $685.13. a. 14.5% b. 6.5% c. 9.3% d. 12.3%

*April 21, 2015*

**math**

Thank you

*April 17, 2015*

**math**

Simplify 6P2 A.30**** B.15 C.12 D.720 Simplify 8c5 A.6,720 B.336 C.56**** D.10

*April 17, 2015*

**Science**

What volume of aluminium has the same number of atoms as 8.0cm^3 of mercury?

*April 16, 2015*

**math**

NVM

*April 13, 2015*

**math**

NO ONE REPLIED.

*April 13, 2015*

**math**

How do i find the 12th term of the sequence 36,18,9.... using a formula

*April 13, 2015*

**math**

THANK YOU SO MUCH REINY.

*April 13, 2015*

**math**

How do i find the 12th term of the sequence 36,18,9.... using a formula

*April 13, 2015*

**math**

t12=36(1/3)^11 36(1/2048) =0.017578125 right or wrong?

*April 13, 2015*

**HELPP**

The volume of a rectangular prism can be computed using the formula V = lwh. What is the width of a prism that has a volume of 1664 cubic centimeters, a length of 16 centimeters, and a height of 8 centimeters? A. 11 cm B. 13 cm C. 26 cm D. 768 cm

*April 7, 2015*

**math**

write the equation of the line: a line that goes through the point (-1,5) and has a slope of 2/3

*April 6, 2015*

**physics**

A 2.50m -long, 450g rope pulls a 10.0kg block of ice across a horizontal, frictionless surface. The block accelerates at 2.50m/s2 . How much force pulls forward on the rope?

*March 27, 2015*

**Physics**

You drop a rock from a 300-meter cliff. How long will it take to reach the ground? Assume it has no significant air resistance

*March 26, 2015*

**Math Help**

A right triangle has a leg B of length 7 and a hypotenuse of length 11. What is the length of the other leg A? Round to the nearest tenth, if necessary. A. 2.0 B. 8.5 C. 13.0 D. 9.6 Please help, I was gone for this lesson, just need someone to explain how they got the answer.

*March 16, 2015*

**Dynamics**

an 800 lb cannon fires a 5 lb cannonball in a horizontal direction. the cannon sits on a skid; the kinetic coefficient of friction between the skid and the horizontal surface is .25. if the cannonball has a speed of 650 ft/s when it leaves the cannon, determine a) the recoil ...

*March 15, 2015*

**algebra**

you research the cost of a gallon of gasoline over several years to look for trends the table shows the data you have collected what is the equation of the line of best fit how much would you expect to pay for gasoline in 2029 a)y=0.538x+1.36; $33.10 b) y=0.289x+1.75:$18.80 C ...

*March 14, 2015*

**algebra**

you research the cost of a gallon of gasoline over several years to look for trends the table shows the data you have collected what is the equation of the line of best fit how much would you expect to pay for gasoline in 2029 a)y=0.538x+1.36; $33.10 b) y=0.289x+1.75:$18.80 C ...

*March 14, 2015*

**Calculus**

A curve passes through the point (7,6) and has the property that the slope of the curve at every point P is 4 times the y-coordinate of P. What is the equation of the curve? Simplify the equation as much as possible.

*March 9, 2015*

**physics**

A painter is pressing a 125g paint pad against the ceiling with a force of 8.3 N at an angle of 30° from the vertical. The pad moves at a constant velocity. What is the coefficient of friction between the pad and ceiling?

*March 5, 2015*

**Energy&Society**

How do i find the fuel cost per energy unit (different energy sources). I don't have to calculate it. I just want to know from where I can get it.

*March 5, 2015*

**Chemistry**

Can we use moles of HCl instead of B to calculate limiting reactant?

*February 27, 2015*

**Chemistry**

When 0.500 moles of boron trichloride react with 1.20 moles hydrogen gas to produce elemental boron and hydrogen chloride gas, the actual yield of boron was 66.4 % of the theoretical yield. The mass of boron obtained was _____ g. Please help I'm stuck on it.

*February 27, 2015*

**physics**

take the answer you get for F and subtract "The engine develops a maximum force of 100 kN" to get the correct answer

*February 25, 2015*

**chemistry**

sodium burns in chlorine to produce sodium chloride according to the reaction: 2Na(s) + Cl2(g) = 2NaCl(s). A student is asked to predict the mass of sodium chloride produced when 71 g of sodium is placed in a container of 200 g of chorine. The container is heated until the ...

*February 23, 2015*

**STAT**

.172

*February 20, 2015*

**S.S.**

what was "king" and the main topic of conversation in the south? politics sugarcane cotton slavery I was thinking COTTON was KING so C

*February 19, 2015*

**science**

can someone explain the life cycle of the animalia kingdom please

*February 11, 2015*

**physics**

a tsunami originating in japan has a wavelength of 10^5 m and a period of 10 mins. how long does it take to travel 8000km?

*February 11, 2015*

**Math**

The company needs at least $300,000 fire and theft insurance and at least $4,200,000 and liability for the from these plans. How many units should be purchased from H plan to minimize the cost of the premiums? What is the minimum premium?

*February 7, 2015*

**physics**

Four identical point charges (+2.51 nC) are placed at the corners of a rectangle, which measures 4.00 m by 7.00 m. If the electric potential is taken to be zero at infinity, what is the potential at the geometric center of this rectangle?

*February 6, 2015*

**Calculus 2**

wouldn't it be the integral of sqrt(1+u^2)du instead of integral u(sqrt (1+u^2)du because the du takes care of the outside u?

*February 4, 2015*

**Calculus 2**

integral of e^x(sqrt(1+e^(2x)))dx

*February 4, 2015*

**Calculus 2**

use the method of equating coefficients. integral of (x^3+5x^2+12)/((x^2)(x^2+4)) dx

*February 4, 2015*

**physics**

Air becomes conducting when the electric field strength in a region exceeds 3x106 V/m. if a spark jumps between a charged object and a grounded object when the two objects are 10 cm apart, what is the potential difference between the two objects? If a lightning strike is 4x103...

*February 2, 2015*

**Physics**

A hollow metal sphere has inner and outer radii of 20.0 cm and 30.0 cm, respectively. As shown in the figure, a solid metal sphere of radius 10.0 cm is located at the center of the hollow sphere. The electric field at a point P, a distance of 15.0 cm from the center, is found ...

*January 29, 2015*

**physics**

A +1.4-nC point charge is placed at one corner of a square (1.8 m on a side), and a -2.5-nC charge is placed on the corner diagonally opposite. What is the magnitude of the electric field at either of the other two corners?

*January 29, 2015*

**algebra**

The mean on a Advanced Algebra test was 78 with a standard deviation of 8. If the test scores are normal distributed, find the interval about the mean that contains 99.7% of the scores. Use the empirical rule.

*January 28, 2015*

**Math, Algebra**

I've done. y-(-3)=(5/2)(x-(-3)) y-(-3)=(5/2(-15/2) y=(5/2x)-(-15/2)+3 y=(5/2x)+(9/2) Is that correct?

*January 19, 2015*

**Math, Algebra**

I normally use point slope. I'm used to having to sets of points not just one.

*January 19, 2015*

**Math, Algebra**

Can someone help me figure this out for my review? Find the equation of the line that passes through (2,-3) and has a slope of (5/2)

*January 19, 2015*

**Chemistry (Error Propagation)**

Calculate, with uncertainty, and express with a reasonable number of significant figures. a) 5.4 (±0.2) – 3.7 (±0.4) = b) 6.84 (±0.04) × 0.7 (±0.04) =

*January 19, 2015*