Sunday

August 2, 2015

August 2, 2015

Total # Posts: 2,234

**physics**

A 50.0-kg box is sliding on a rough horizontal floor, and the only horizontal force acting on it is friction. You observe that at one instant the box is sliding to the right at 1.5 m/s and that it stops in 2.5 s with uniform acceleration. What magnitude force does friction ...
*February 14, 2013*

**Trig/precalc**

Cos[x + (7 Pi)/4] + Cos[x - (7 Pi)/4] = 1
*February 12, 2013*

**Calculus**

ok thank you
*February 11, 2013*

**Calculus**

Find the derivatives of the function k(x)=sqrt(sin(2x))^3 I think I have the answer and was wondering if i had it correct k'(x)=2sin(x)^3+8sin(x)
*February 11, 2013*

**calculus**

Find the derivatives of the functions k(x)=(x^3+e^x)^4
*February 11, 2013*

**Spanish**

Translate: I have a big nose. Is it: Tengo la nariz grande. or : Tengo una nariz grande. My teacher says you must use el, la, los, and las with body parts.
*February 10, 2013*

**physics**

A golfer hits a shot to a green that is elevated 3.00 m above the point where the ball is struck. The ball leaves the club at a speed of 16.1 m/s at an angle of 52.0¢ª above the horizontal. It rises to its maximum height and then falls down to the green. Ignoring air...
*February 8, 2013*

**math-trig**

tan(t)-sec^2(t)/tan(t)
*February 8, 2013*

**Languege arts**

Nice job helper i needed help with that and u got them all right thanks! :)
*February 7, 2013*

**math**

13 2/9 - 8 8/9
*February 7, 2013*

**math**

13 2/9 - 8 8/9
*February 5, 2013*

**math**

Hello. I am having a little bit of touble with algebra, distributive property. The question is -20 (19-a) can you please help?! Thanks!
*February 4, 2013*

**Spanish**

I need to decide if these capitalized words are preterite or imperfect and I just don't get it. Could someone help me out please? Here is the story: I need help with this story. Could you please tell me if the words that are in all CAPITAL letters are preterite or ...
*February 4, 2013*

**algebra**

determine the given quadratic function has a minimum valueor maximum vale. Then find the coordinates of the minimum or maximum point. f(x)=x^2=2x-9
*February 4, 2013*

**Intro to Computer Engineering**

When solving 5x^2-50x+125=0, a space alien got x=8 for one of the two roots. What possible base could the alien be using? (Note: the coefficients are also in this base. That is 5,50,125 are all in this mystery base as well)
*January 31, 2013*

**Chemistry**

The program still states this is incorrect
*January 30, 2013*

**Chemistry**

You carry out an exothermic reaction inside a Styrofoam cup calorimeter, using a temperature probe to monitor the temperature throughout the reaction. You find that the temperature increases 7.40 °C during the reaction. The specific heat of the reaction solution is known ...
*January 30, 2013*

**math**

write the hidden question or questions in the problem Billy Bob wins $500 in a school raffle. He decides to keep $120 for himself, give $60 to charity, and divide the rest equally among his 5 brothers & sisters. How much will each brother zor sister Recieve from billy bob?
*January 28, 2013*

**Biology**

In a population of jaguars, a gene with two alleles encodes the fur color. Allele B causes melanism (dark fur) and is dominant over allele b, which results in light colored fur. Suppose that there is a migration event, producing a population with 60% BB, 20% Bb and 20% bb ...
*January 28, 2013*

**Pre calc**

Please finish y+7=6/7x-30/7
*January 25, 2013*

**Physics**

a) If the lizard has a specific heat of 4.2 J/(g x C), what is rate of increase of the lizard’s temperature? (b) Assuming that there is no heat loss by the lizard (to simplify), how long must the lizard lie in the sunlight in order to raise its temperature by 5.0 C?
*January 19, 2013*

**Physics**

A lizard of mass 3.0 g is warming itself in the bright sunlight. It casts a shadow of 1.6 cm^2 on a piece of paper help perpendicularly to the Sun’s rays. The intensity of sunlight at the Earth is 1.4 x 10^3 W/m^2, but only half of this energy penetrates the atmosphere ...
*January 19, 2013*

**Physics**

A 20 g lead bullet leaves a rifle at a temperature of 47 degrees celcieus and travels at a velocity of 500 m/s until it hits a large block of ice at 0 degrees celcuis and comes to rest within it. How much ice will melt?
*January 19, 2013*

**Chemistry**

if the H+ in acid mine drainage is 6.3 x 10^-5 mol/L, the pH of the drainage water is ___. It would require ___ gal of 0.1 M Ca(OH)2 (2 is a subscrip) to neutralize the proton acidity in 1000 gal of such drainage water.
*January 19, 2013*

**Mechanics....Urgent!!**

Find the magnitude and direction of the equilibrant of two forces, one being horizontal pull of 18 N and the other a pull of 23 N at 50 degrees to the 12 N force.
*January 16, 2013*

**Mechanics & hydromechanics**

Find the magnitude and direction of the equilibrant of two forces, one being horizontal pull of 18 N and the other a pull of 23 N at 50 degrees to the 12 N force.
*January 16, 2013*

**Mechanics & hydromechanics**

Three forces pulling on a body are in equilibrium. The direction of one is due south, the direction of another is 80 degrees east of north, and the third force acts in the direction of 35 degrees west of north. If the magnitude of southerly force is 38 N, find the magnitudes ...
*January 16, 2013*

**Mechanics & hydromechanics**

A uniform 98 N pipe is used as a lever. Where the fulcrum must be placed if a 504 N weight at one end is to balance a 192 N weight at the other end?
*January 16, 2013*

**Mechanics & hydromechanics**

A uniform plank AB of length 4.6 m and weight 508 N is suspended by a vertical rope at each end.A girl of weight 305 N stands in the position 1.6 m from one end.Calculate the tension in the rope at one end using the other end as axis of rotation.
*January 16, 2013*

**Mechanics & hydromechanics**

Where a 1208 N weight must be hung on a uniform 214 m pole so that a boy at one end supports one-third as much as a man at the other end.
*January 16, 2013*

**Mechanics & hydromechanics**

A block of wood is pulled along a Horizontal table by a force of 33 N inclined at 30 degrees above the Horizontal.Find the vertical and horizontal components of the force.
*January 14, 2013*

**Mechanics & hydromechanics**

Three forces pulling on a body are in equilibrium.The direction of one is due south, the direction of another is 80 degrees east of north, and the third force acts in the direction of 35 degrees west of north.If the magnitude of the southerly force is 38 N, Find the magnitude ...
*January 14, 2013*

**Mechanics & hydromechanics**

Find the magnitude and direction of the equilibrant of two forces, one being a horizontal pull of 18 N and the other a pull of 23 N at 50 degrees to the 12 N force.
*January 14, 2013*

**biochemistry**

-1.70
*January 13, 2013*

**math**

name the property 32X4=(30X4)+(2X4)
*January 8, 2013*

**physics**

If A = 4 units north, B = 4 units east, and C = 6 units northeast (45o east of north), click on the figure to find A + B + C. Construct the figure.
*January 8, 2013*

**Calc**

A rock is thrown upwards (vertically) from the ground with an initial velocity of 40 feet per second. If acceleration due to gravity is -10 feet per second squared, how high will the rock go?
*January 8, 2013*

**monomials and polynomials**

simplyfy in two steps by removing parathensis (4xy-3y^3)_(xy+y^2)
*January 7, 2013*

**Algebra 1**

An airplane travels 6200 km against the wind in 8 hours and 7080 km with the wind in the same amount of time. What is the rate of the plane in still air and what is the rate of the wind?
*December 21, 2012*

**algebra**

2.7q - 2.3 -2.6q = -0.9q -1.6
*December 19, 2012*

**Physics**

A 4 kg block rests between the floor and a 3 kg block. The 3 kg block is tied to a wall by a horizontal rope. If the coefficient of static friction is 0.800 between each pair of surfaces in contact, what force must be applied horizontally to the 4 kg block to make it move?
*December 19, 2012*

**Math**

78.50
*December 17, 2012*

**Math**

it doed say to the tenths
*December 17, 2012*

**Math**

6.753=7.000 78.456=80.00
*December 17, 2012*

**Math**

6.750 78.46
*December 17, 2012*

**Math**

round to the given place 6.64 (tenths) 2.435 (hundredths) 6.753 (ones) 78.456 (tenths)
*December 17, 2012*

**math**

how do I do long division
*December 14, 2012*

**Math**

Thank you both
*December 13, 2012*

**Math**

Ok. My answer was 105mins But converted to 1hr & 45 mins. Thanks!
*December 13, 2012*

**Math**

That's what I got & my teacher marked it wrong. Is that 1hr & 45 mins
*December 13, 2012*

**Math**

Meredith took 15 minutes to unpack 4 boxes of books. If she unpacked a total of 28 boxes, how long did it take her to unpack all the boxes?
*December 13, 2012*

**math**

This is completely incorrect. This is assuming that the price of one television equals the price of one dvd. Since it tells you that one television equals two dvds, you substitute in 4 dvds for two televisions. So you pretend that there are seven dvds. So the price of one dvd ...
*December 13, 2012*

**math**

- Three hockey teams, the Crabs, the Eels, and the Seals, played each other once with no shutouts ( every team scored at least 1 goal in each game). A team gets 10 points for a win, 5 point for a tie and one point for each goal scored. If the Crabs received 20 points, the Eels...
*December 12, 2012*

**math**

- Three hockey teams, the Crabs, the Eels, and the Seals, played each other once with no shutouts ( every team scored at least 1 goal in each game). A team gets 10 points for a win, 5 point for a tie and one point for each goal scored. If the Crabs received 20 points, the Eels...
*December 12, 2012*

**sociology**

which sociological approach focuses on the macrolevel and would tend to view inequality in gender as central to behavior and organization?
*December 11, 2012*

**Math**

Solve 2×2×2×3×7
*December 10, 2012*

**accounting**

Use your knowledge of income statements to fill in the missing items: Sales Cost of goods sold $575,000 Gross profit $1,600,000 General and administrative expense $200,000 Selling and marketing expense $ Depreciation $50,000 Operating income $ Interest $100,000 Income before ...
*December 8, 2012*

**math**

113,333.33
*December 7, 2012*

**physics**

A thin spherical shell of mass 0.450 kg and diameter 0.190 m is filled with alcohol (ρ = 806 kg/m3). It is then released from rest on the bottom of a pool of water. Find the acceleration of the alcohol filled shell as it rises toward the surface of the water.
*December 5, 2012*

**physics**

A thin spherical shell of mass 0.450 kg and diameter 0.190 m is filled with alcohol (ρ = 806 kg/m3). It is then released from rest on the bottom of a pool of water. Find the acceleration of the alcohol filled shell as it rises toward the surface of the water.
*December 5, 2012*

**Fractions**

What if u have 71/10 and u have to Chang that in to a mixed number
*December 4, 2012*

**Math**

Estimate each quotient 766÷8 $31.75÷8
*December 3, 2012*

**Chemistry**

How many hours are required for the deposition of 15.0 grams of Al from molten AlCl3 by a current of 15.0 amps?
*December 3, 2012*

**Chemistry**

What is the molar mass of a compound if a gaseous sample has a density of 2.807 g/L at 18 °C and 728 torr?
*December 1, 2012*

**Chemistry**

Dimethylamine burns in oxygen according to the following equation: 4 C2H7N + 15 O2 → 8 CO2 + 14 H2O + 2 N2 (a) How many liters of O2 at 35 °C and 0.840 atm will be needed to burn 7.70 L of C2H7N at 35 °C and 0.840 atm? (b) How many liters of CO2 at 35 °C and ...
*December 1, 2012*

**Physics**

A 17kg child slides down a 2.7m -high playground slide. She starts from rest, and her speed at the bottom is 1.8 m/s. What is the change in the thermal energy of the slide and the seat of her pants?
*November 30, 2012*

**Physics**

A car is traveling at 10 m/s. By what factor does the car's kinetic energy increase if its speed is doubled to 20 m/s?
*November 30, 2012*

**Physics**

An object is placed 4 cm in front of a concave lens of focal length 3 cm. Using the lens equation, find where the image will form and state whether it is a real or virtual image.
*November 30, 2012*

**Math**

A high school volleyball team has 20 members. If there is an equal number of members from each of the 4 grades, how many students from each grade are on the team?
*November 29, 2012*

**math**

how many minutes are there in 6 hours and 45 minutes
*November 27, 2012*

**math**

Chances are 50-50 that a newborn baby will be a girl. For families with five children, what is the probability that all the children are girls
*November 24, 2012*

**statistics**

Each of the following is a confidence interval for u = true average(population mean) resonance frequency (Hz) for all tennis rackets of a certain type: (114.4, 115.6) (114.1, 115.9) A) What is the value of the sample mean resonance frequency? B) Both intervals were calculated ...
*November 23, 2012*

**statistics**

Each of the following is a confidence interval for u = true average(population mean) resonance frequency (Hz) for all tennis rackets of a certain type: (114.4, 115.6) (114.1, 115.9) A) What is the value of the sample mean resonance frequency? B) Both intervals were calculated ...
*November 23, 2012*

**statistics**

Random samples of size n=10 are taken from a normal population whose statndard deviation is known to be 5. Calculate the area under the sampling distribution curve for x bar between the points u-1 and u+1. That is find the probability that the sample mean lies within + or = 1 ...
*November 23, 2012*

**statistics**

Random samples of size n are selected from a normal population whose standard deviation is know to be 2. Suppose you want 90% of the area under the sampling distribution of x bar to lie within + or - 1 unit of a population mean u. Find the minimum sample size n that satisfies ...
*November 23, 2012*

**physics**

a longitudinal wave with a frequency of 3.0 Hz takes 1.7 s to travel the length of a 2.5-m slinky (see figure 16.3). Determine the wavelength of the wave.
*November 19, 2012*

**physics**

a longitudinal wave with a frequency of 3.0 Hz takes 1.7 s to travel the length of a 2.5-m slinky (see figure 16.3). Determine the wavelength of the wave.
*November 18, 2012*

**physics**

Suppose the sound is emitted uniformly in all directions by a public address system. The intensity at a location 22 m away from the sound source is 3.0 x 10-4 W/m2. What is the intensity at a spot that is 78 m away?
*November 18, 2012*

**physics**

light is an electromagnetic wave and travels at a speed of 3.00 x 108 m/s. the human eye is most sensitive to yellow-green light which has a wavelength of 5.45 x 10-7 m. what is the frequency of this light?
*November 18, 2012*

**physics**

at a distance of 3.8 m from a siren, the sound intensity is 3.6 x 10-2 W/m2. Assuming that the siren radiates sound uniformly in all directions, find the total power radiated.
*November 18, 2012*

**physics**

the distance between a loudspeaker and the left ear of a listener is 2.70 m a) calculate the time required for sound to travel this distance if the air temperature is 20oC. b) assuming that the sound frequency is 523 Hz, how many wavelengths of sound are contained in this ...
*November 18, 2012*

**physics**

From a vantage point very close to the track at a stock car race, you hear the sound emitted by a moving car. You detect a frequency that is 0.86 times as small as that emitted by the car when it is stationary. The speed of sound is 343 m/s. what is the speed of the car?
*November 18, 2012*

**math**

a particle starts at time t = 0 and moves along the x - axis so that its position at any time t is greater than or equal to zero is given x(t) = (t-1)^3(2t-3) A. Find the velocity of the particle at any time t greater than or equal to 0. B. For what values of t is the velocity...
*November 15, 2012*

**Math**

What is another way to write the expression 44n? 44÷n?
*November 14, 2012*

**Pre-Algebra**

A bag contains 10 white golf balls and 6 striped golf balls. A golfer wants to add 112 golf balls to the bag. He wants the ratio of white to striped golf balls to remain the same. How many of each should he add?
*November 14, 2012*

**math**

Write four million, four thousand, forty in standard form.
*November 14, 2012*

**math**

Order the following numbers from greatest to least. 2.071; 20.071; 20.71 Is this right 20.71; 20.071; 2.071
*November 13, 2012*

**Math**

Without multiply how many decimals places r in the product of 4.97 and 3.456?
*November 12, 2012*

**math**

Isn't 19 + 21 + 40 which is more than the amount of children in the class? Then you add 10 more that don't play it's 50. So how is the class total 38 as implied?
*November 10, 2012*

**math**

rene gave each of six people 1/10 of a veggie pizza. rene has 2/5 of the pizza left. explain how this is true
*November 8, 2012*

**science**

How much total work is done by 450-N girl who lifts a 52-N backpack 1.2m to her shoulders and then climbs a ladder 3.0m high?
*November 7, 2012*

**physics**

From the moment a 42 m/s fastball touches the catcher's mitt until its completely stopped takes 0.014 s. Calculate the average acceleration of the ball as it is being caught.
*November 6, 2012*

**math**

a pizza place sold worth 2000 of pizza on saturday. there were 29 small pizzas sold and medium pizzas sold
*November 5, 2012*

**physics**

A paperweight weighs 6.9N in air. When it is completely submerged in water it appears to weigh 4.3N. A) What is the volume of the paperweight? B) What is the density paperweight? The density of water is 1000kg/m3.
*November 4, 2012*

**physics**

A 2000 kg truck is at rest at a stop sign. A 1100kg car collides head-on with the truck. The car was moving at 15.0m/s before the collision if the collision was completely inelastic, what is the velocity of the car and the truck after the collision?
*November 4, 2012*

**physics**

A paperweight weighs 6.9N in air. When it is completely submerged in water it appears to weigh 4.3N. A) What is the volume of the paperweight? B) What is the density paperweight? The density of water is 1000kg/m3.
*November 4, 2012*

**physics**

A fulcrum is placed under the center of a uniform 4.00m long, 3.00kg board. Child A has a mass of 42 kg. This child sits on the left end of the board; Child B has a mass of 26kg. Child B sits on the right end of the board. Where should child C (mass 21 kg) sit in order to have...
*November 4, 2012*

**physics**

A paperweight weighs 6.9N in air. When it is completely submerged in water it appears to weigh 4.3N. A) What is the volume of the paperweight? B) What is the density paperweight? The density of water is 1000kg/m3.
*November 4, 2012*

**physics**

A 2000 kg truck is at rest at a stop sign. A 1100kg car collides head-on with the truck. The car was moving at 15.0m/s before the collision if the collision was completely inelastic, what is the velocity of the car and the truck after the collision?
*November 4, 2012*