Thursday

October 20, 2016
Total # Posts: 2,350

**math**

Solve the following system by matrix reduction. Write your answer using parameter(s) if necessary. If there is no solution, state "no solution". x-2y-3z=-2 4x-3y+3z=-8

*November 30, 2015*

**math**

Solve the following system by matrix reduction. Write your answer using parameter(s) if necessary. If there is no solution, state "no solution". x-2y-3z=-2 4x-3y+3z=-8

*November 30, 2015*

**Math**

If log 3=a, log 5=b and log 7=c, express log_{15} 7 in terms of a,b and c.

*November 30, 2015*

**Physics**

The circular blade on a radial arm saw is turning at 293 rad/s at the instant the motor is turned off. In 17.9 s, the speed of the blade is reduced to 60 rad/s. Assume the blade to be a uniform solid disk of radius 0.17 m and mass 0.400 kg. Find the magnitude of the net torque...

*November 28, 2015*

**college algebra**

In a certain gear, a bicycle tire with a diameter of 27 inches makes 3 complete revolution of the pedal.If a cyclist is pedaling at a rate of 100 revolutions per minute, find the speed of the bicycle in miles per hour?

*November 24, 2015*

**Physics [Help, need answer in 10 min]**

During a solar eclipse, the moon (of mass 7.36 × 1022 kg), Earth (of mass 5.98 × 1024 kg), and Sun (of mass 1.99 × 1030 kg) lie on the same line, with the moon between Earth and the Sun. What gravitational force is exerted on the moon by the Sun? The ...

*November 19, 2015*

**physics**

82.069N Just input that as your right answer ;)

*November 18, 2015*

**physics**

A 5.9 kg bucket of water is raised from a well by a rope. The acceleration of gravity is 9.81 m/s/s If the upward acceleration of the bucket is 4.1 m/s/s, find the force exerted by the rope on the bucket of water. Answer in N

*November 18, 2015*

**statistics**

A researcher is interested in manual dexterity of a group of adults, part of study involves asking the participants to complete a task and you a presented with the following information about the length of time taken to complete it in minutes Mean=20 Sd=4 Assuming that the ...

*November 15, 2015*

**Math**

Thanks for the help I really appreciate it.

*November 8, 2015*

**Math **

This is the second part of a two part question for an online class. It gave me the degree and the zeros and I had to give the factored form. I got that part right, but I need to know how to get the expanded form from the factored form. I have several more questions like this ...

*November 8, 2015*

**Physics**

An athlete swings a 3.06 kg ball horizontally on the end of a rope. The ball moves in a circle of radius 0.82 m at an angular speed of 0.25 rev/s. What is the tangential speed of the ball? Answer in units of m/s.

*November 3, 2015*

**trig**

Find the magnitude and direction angle of the vector v. v = 4(cos 125°i + sin 125°j) ||v|| = θ =

*November 2, 2015*

**math**

write an equation that I can use to find the distance I can drive on any number of gallons of gas

*October 29, 2015*

**chemistry**

Calculate the mass of oxalic acid needed to prepare 150 ml of 0.442 M C2H2O4

*October 27, 2015*

**Chemistry**

Solved it. 1:200 is 0.005 g, therefore you multiply it by 1000 mg/g to get mg. You then multiply it by 10 ml to get you the total amount of miligrams, which equals 50 mg.

*October 23, 2015*

**Chemistry**

How many grams of drug X are in 10 mL of a 1:200 solution of X?

*October 23, 2015*

**physics**

Some nucleus of 74X189 (atomic mass = 188.96191 u) undergoes - decay to become 75X189 (atomic mass = 188.95922 u). What is the energy (in MeV) released in this process?

*October 22, 2015*

**physics**

The number of radioactive nuclei present at the start of an experiment is 3.27 x 1015. The number present twenty days later is 7.66 x 1014. What is the half-life (in days) of the nuclei?

*October 22, 2015*

**physics is this correct**

What is the radius of a real or imaginary nucleus of 46X100 do I use the formula R = R_o * A^(1/3) and therefore (1.3*10^-15)* 100^(1/3) =6.0340655e-15?

*October 22, 2015*

**physics**

thankyou could you help me with what formula you used plz

*October 22, 2015*

**physics**

The refractive indices of materials A and B have a ratio of nA/nB = 1.68. The speed of light in material A is 1.26 x 108 m/s. What is the speed of light in material B

*October 22, 2015*

**physics**

An object is located 27.6 cm to the left of a converging lens whose focal length is 46.5 cm. (a) Determine the image distance and (b) the magnification.

*October 22, 2015*

**physics formula check please**

A mirror produces an image that is located 28.0 cm behind the mirror, when the object is located 9.90 cm in front of the mirror. (a) What is the focal length of the mirror? (b) Is the mirror 1 - concave or 2 - convex? (Give the number of the correct answer.) The refractive ...

*October 21, 2015*

**Physics please help**

An object that is 31 cm in front of a convex mirror has an image located 16 cm behind the mirror. How far behind the mirror is the image located when the object is 24 cm in front of the mirror? do I use the formula 1/f = 1/di + 1/do?? please help

*October 21, 2015*

**Math**

16-4c=20

*October 18, 2015*

**Physics**

A model airplane has a mass of 0.95 kg and moves at a constant speed on a circle that is parallel to the ground. Assume that there is no upward lift on the plane generated by its wings. Without such lift, the guideline slopes downward due to the weight of the plane. Find the ...

*October 16, 2015*

**English**

Identify the correct sentence. A. A giant spider with long legs are crawling on the wall in the living room. B. A giant spider with long legs is crawling on the wall in the living room. C. Neither the roach nor the spider are still alive. D. Neither the spider nor the roaches ...

*October 15, 2015*

**English**

Thanks

*October 15, 2015*

**English**

Identify the incorrect sentence. A. There is a good variety of mugs in the cabinet. B. There are a good variety of mugs in the cabinet. C. A number of glasses have been broken. D. The number of broken glasses has increased.

*October 15, 2015*

**maths**

6.79

*October 15, 2015*

**Algebra**

-4(a+3)-a

*October 14, 2015*

**Math 208 (Linear)**

a person purchased a $142,819 home 10 years ago by paying 15% down and signing a 30-year mortgage at 10.5% compounded monthly. Interest rates have dropped and the owner wants to refinance the upaid balance by signing a new 15-year mortgage at 6.3% compounded monthly. How much ...

*October 12, 2015*

**physics**

A container holds 1.9 mol of gas. The total average kinetic energy of the gas molecules in the container is equal to the kinetic energy of a 8.0x10-3 kg bullet with a speed of 960 m/s. What is the Kelvin temperature of the gas? do I use the formula? T= (mv^2)/u No 3k

*October 12, 2015*

**Physics**

Identical +2.83 μC charges are fixed to adjacent corners of a square. What charge (magnitude and algebraic sign) should be fixed to one of the empty corners, so that the total potential at the remaining empty corner is 0 V? φ =k•q/r φ1+ φ2 + φ3 =0...

*October 12, 2015*

**Math**

(X+4)^2=3 X^2+8x+16-3=0 X^2+8x+13=0 Use quadratic formula X=(-8±sqrt(64-4*13))/(2) =-(8±sqrt(12))/2 =-4±sqrt (3)

*October 11, 2015*

**Chemistry**

Calculate Delta H for the reaction CH4(g)+NH3(g)-->HCN(g)+3H2(g) given, N2(g)+3H2(g)->2NH3(g) DeltaH=-91.8kj C(s)+2H2(g)->CH3(g) DeltaH=-74.9kj h2(g)+2C(s)+N2(g)->2HCN(g) DeltaH=270.3kj

*October 11, 2015*

**maths**

if it takes 8 men 3 hours to clean a house, how many men would it take to get job done in 2.5 hours

*October 11, 2015*

**Physics **

A container holds 1.9 mol of gas. The total average kinetic energy of the gas molecules in the container is equal to the kinetic energy of a 8.0x10-3 kg bullet with a speed of 960 m/s. What is the Kelvin temperature of the gas? do I use the formula? T= (mv^2)/u No 3k

*October 10, 2015*

**math**

When the movie is half over, popcorn sells for half price. Full price popcorn is $3.50, and drinks are $1.35. Determine the cost for purchasing 3 orders of popcorn and 3 drinks when the movie is half over. $

*October 3, 2015*

**chemistry equilibrium **

phsophorous trichloride and phosphorous pentachloride equilibrate in the presence of molecular chlorine according to PCl3 (g) +Cl2 (g)->PCl5 (g) Kc = 2.01 at 500k If a 1.000L reaction vessel is charged with .300 mol of PCl5(g) and allowed to equilibrate at this temperature...

*October 1, 2015*

**chemistry**

phsophorous trichloride and phosphorous pentachloride equilibrate in the presence of molecular chlorine according to PCl3 (g) +Cl2 (g)->PCl5 (g) Kc = 2.01 at 500k If a 1.000L reaction vessel is charged with .300 mol of PCl5(g) and allowed to equilibrate at this temperature...

*October 1, 2015*

**calc 2**

A loaf of bread is removed from an oven at 350 degrees F and cooled in a room whose temperature is 70 degrees F. If the bread cools to 210 degrees F in 20 minutes, how much longer will it take the bread to cool to 155 degrees F. Round to the nearest minute.

*September 29, 2015*

**maths**

I need explanation to this question.solve 48 base12 multiply by 15 base12.i can solve it by first converting to base ten and back to base 12,but i need to be able to solve directly in base12.Thanks

*September 29, 2015*

**Biology**

You find 3 trees where each tree gives a different coloured fruit: red, pink or orange. You perform crosses between all three trees and get the following results: P: red x pink ---F1: ½ red: ½ pink P: red x orange --- F1: ½ red: ½ orange P: pink x ...

*September 27, 2015*

**Physics**

Thank you so much!!!!

*September 27, 2015*

**Physics**

A fireman d = 33.0 m away from a burning building directs a stream of water from a ground-level fire hose at an angle of θi = 21.0° above the horizontal as shown in the figure. If the speed of the stream as it leaves the hose is vi = 40.0 m/s, at what height will the ...

*September 27, 2015*

**Art**

city street by herman maril

*September 17, 2015*

**information technology**

write a pascal program which reads price of an item. the program should compute 25% discount on the original price, it should display the discounted amount and the discounted price of an item.

*September 16, 2015*

**Physics**

You toss a tennis ball straight upward. At the moment it leaves your hand it is at a height of 1.5 m above the ground, and it is moving at a speed of 7.8 m/s. (a) How much time does it take for the tennis ball to reach its maximum height? (b) What is the maximum height above ...

*September 16, 2015*

**physics**

A quarterback takes the ball from the line of scrimmage, runs backward for 18.0 yards, then runs sideways parallel to the line of scrimmage for 16.0 yards. At this point, he throws a 49.0-yard forward pass straight down the field. What is the magnitude of the football’s ...

*September 16, 2015*

**physics**

Vector B~ has x, y, and z components of 9.6, 6, and 8.5 units, respectively. Calculate the magnitude of B~ .

*September 16, 2015*

**physics**

A descent vehicle landing on the moon has a vertical velocity toward the surface of the moon of 34.1 m/s. At the same time, it has a horizontal velocity of 53.5 m/s. At what speed does the vehicle move along its descent path? Answer in units of m/s.

*September 16, 2015*

**physics**

Bob heads out into a lake at an angle of 27◦ with respect to the shore. If his boat is capable of a speed of 1.3 m/s, how far from land will he be in 2 min and 28 s ? Answer in units of m.

*September 16, 2015*

**CHEM**

The following data were collected for determining the concentration of suspended solids in a water sample. (D= 1.01 g/mL). Express all calculated data with the correct number of significant figures. Volume of sample (mL): Trial 1: 25.0 trial 2: 20.0 trial 3: 50.0 trial 4: 25.0...

*September 15, 2015*

**algebra**

sorry Isiah is C. 0.625

*September 15, 2015*

**algebra**

Are you serious sue i have been reading some of his math questions and all I see at the end is your dumb ass saying what chart, what graph, duh its 12 or obvious don't see a graph. and now your telling him how to make profiles wtf. get a life sue if your not going to help ...

*September 15, 2015*

**physics**

As soon as a traffic light turns green, a car speeds up from rest to 50.0 mi/h with constant acceleration 7.50 mi/h-s. In the adjoining bike lane, a cyclist speeds up from rest to 17.0 mi/h with constant acceleration 14.50 mi/h-s. Each vehicle maintains constant velocity after...

*September 15, 2015*

**chem**

oh, i am sorry. I meant "data"

*September 14, 2015*

**chem**

The following state were collected for determining the concentration of suspended solids in a water sample. (D= 1.01 g/mL). Express all calculated data with the correct number of significant figures. Volume of sample (mL): Trial 1: 25.0 trial 2: 20.0 trial 3: 50.0 trial 4: 25....

*September 14, 2015*

**Math 10**

What is the circumference of the largest circle you could cut from a 30 cm by 20 cm sheet of paper? What area of paper would you cut away. PLZ HELP GUYS TEST TOMMOROW OH MA GAWD!

*September 14, 2015*

**Chem**

A 25.0 mL aliquot of a well-shaken and filtered sample of river is pipetted into an evaporating dish. The sample was heated to dryness. Assume the density of the river water was 1.01g/mL. The following data were collected for Trial 1. Complete the data. Record values with the ...

*September 14, 2015*

**Chem**

The following state were collected for determining the concentration of suspended solids in a water sample. (D= 1.01 g/mL). Express all calculated data with the correct number of significant figures. Volume of sample (mL): Trial 1: 25.0 trial 2: 20.0 trial 3: 50.0 trial 4: 25....

*September 14, 2015*

**Math**

Oh an also how do I solve this. 9 x (7-16) + 9

*September 14, 2015*

**Math**

Translate the following sentence into math symbols. Then solve the problem. y more than 4 is -36 My answer: 4 + y = =36 y = -40? Did I answer both of the questions right?

*September 14, 2015*

**Math**

I found out 2000 ml is not necessary knowledge to answer the equation. You simply do the following: (500g dextrose) * (100 ml solution/70g dextrose) = 714.29 ml

*September 13, 2015*

**Math**

A nutritional formula calls for 500 g of dextrose in a total volume of 2000 ml. how many milliliters of a 70% w/v dextrose injection are needed to provide the required amount of dextrose? This seems to be a dimensional analysis problem. We have: 500g/2000ml 70% w/v = 70 g ...

*September 13, 2015*

**Chemistry**

In the reaction, PCl3 + Cl2 ------> PCl5 the concentration of the reactants at equilibrium were each determined to be 7.2 mol/L, and the product at 0.050 mol/L. Calculate the equilibrium constant (rounding to 2 significant figures and using scientific notation), and state ...

*September 13, 2015*

**physics**

A 4000 kg trailer is towed up a hill with a 5% grade. If the towing truck starts from rest at the bottom of the hill and reaches a speed of 12 m/s at the top of the hill, how much is the towing force. The road from the bottom to the top of the hill is straight with a length of...

*September 11, 2015*

**Science**

the first one is c

*September 10, 2015*

**Science**

2 is D

*September 10, 2015*

**Science**

whats the answer ?

*September 9, 2015*

**physics**

a 60-kg student travelling in a 1000 kg car with a constant velocity has a kinetic energy of 1.2 *10^4 J. What is the speedometer reading of the car in km/h?

*September 3, 2015*

**Algebra**

For #3 wouldn't it be t-2 or something because it is 2 hours into trip

*August 31, 2015*

**Pre-Calculus**

Yes but it would be y=(9/5)x+32 Parentheses

*August 31, 2015*

**Maths**

A house plan shows a scale of 1:25. If the rectangular lounge room of the house is to measure 4 metres by 6 metres, what will the area of the lounge room be on the plan?

*August 30, 2015*

**math**

75x+55x=182 where x is time in hours 130x = 182 X=182/130

*August 29, 2015*

**calc**

2) would be y=8x+1/2 3) would be y=-6x+12 No 1 is correct

*August 29, 2015*

**language arts**

What can be inferred about how the Maori feel about the land they live on?

*August 28, 2015*

**Physics**

The height of a cylindrical container is 15 cm and the inside diameter of the container is 10 cm. a) what is the volume? b) How much weight (in kg) would be required to fill the container to a density of 1.3 g/cm^3?

*August 27, 2015*

**History**

C B A

*August 24, 2015*

**Trig**

Find all solutions of the equation in the interval [0,2pi). 2sin theta+1=0. Write answer in radians in terms of pi.

*August 19, 2015*

**math**

Thanks Damon. Now I understand the concept of it.

*August 19, 2015*

**math**

all of the following are coordinates on the same straight line except: A) (0,2) B) (3,11) C) (5,15) D) (7,23) E) (x,3x+2)

*August 19, 2015*

**physics**

A certain bacterium swims with a constant speed of 4.61 µm/s. How long will it take to swim across a petri dish that has a diameter of 8.69 cm?

*August 17, 2015*

**Life sciences**

1.Clear lime water turned milky after it was exposed to exhaled air

*August 17, 2015*

**Algebra**

Rewrite each expression with positive exponents and simplify. X^2•x^n/x^3•x^n What does this question mean? Do I just cancel things out? Please help

*August 15, 2015*

**Algebra**

Use absolute value notation. The distance between x and -10 is at least 6. |x-(-10)|>or=6 Is that notation correct?

*August 15, 2015*

**math**

edgar earns 200 dollars a week plus a 15% commission on all sales over 1,000 dollars.if edgar sells for one week or 2,500 dollars what is his gross pay for that one week.

*August 15, 2015*

**math**

a certain alloy contains 5.25% cooper. how much cooper is there in a piece weighing 200 pounds.

*August 15, 2015*

**math**

paul can type 60 words per minute and jenifer can type 80 words per minute how does pauls typing speed compare to jenifers

*August 15, 2015*

**pre-cal**

please help, step by step having difficulty here as well. Find the term containing x5 in the expansion of (x + 2y)^10

*August 12, 2015*

**pre-cal**

Use Pascal's triangle to expand the expression. (x − y)5 so I tried to work this out: (x-y)^5 = [(x-y)(x-y)][(x-y)(x-y)](x-y) (x-y)^2 = (x-y)(x-y) = x^2 - 2xy + y^2 x^2 - 2xy + y^2)(x^2 - 2xy + y^2) = x^4 -4x^3y + 6x^2y^2 - 4xy^3 + y^4 I am still confused can any ...

*August 12, 2015*

**physics**

A model rocket blasts off from the ground, rising straight upward with a constant acceleration that has a magnitude of 87.9 m/s2 for 1.51 seconds, at which point its fuel abruptly runs out. Air resistance has no effect on its flight. What maximum altitude (above the ground) ...

*August 12, 2015*

**Organic Chemistry (University)**

We're supposed to try and figure out the structure of a compound based off the the following information: δ: 2.4 2H triplet δ: 2.1 3H singlet δ: 1.5 2H triplet δ: 1.3 6H singlet δ: 0.9 3H triplet >δ: 2.4 2H triplet This is probably a CH2 ...

*August 11, 2015*

**physics**

What is the magnitude of the average acceleration of a skier who, starting from rest, reaches a speed of 10.5 m/s when going down a slope for 3.18 s?

*August 11, 2015*

**physics**

A hot-air balloon is rising upward with a constant speed of 3.29 m/s. When the balloon is 3.38 m above the ground, the balloonist accidentally drops a compass over the side of the balloon. How much time elapses before the compass hits the ground?

*August 11, 2015*

**Language Arts**

What lesson or meaning do you think the story "The Mark of the Beast" by Rudyard Kipling, held for the British audience of the Victorian era?

*July 26, 2015*

**US Government**

So on my study guide for a final I have this: In Gideon v. Wainwright, d___ _______ rights were the main issue in this Supreme Court case. I Don't know if it's defense attorney rights, or what, but I know this case gave the right to counsel and I'm just very ...

*July 21, 2015*