Friday

September 30, 2016
Total # Posts: 2,819

**Math**

The diameter of my trundle wheel is 50cm. I use it to measure the length of the school park. It rotates 87 times. What is the length of the car park, to the nearest metre?

*September 28, 2016*

**science**

How do I make an acrostic poem for reactants?

*September 28, 2016*

**Calculus**

Find the set of points that the following function is continuous at them . f(x)= { (2x+1)/(x+3) if x<0 (√(x+4)-2)/2x^2-3xx if x>0 -1/3 if x=0

*September 25, 2016*

**Calculus **

Find all the values of a and b in such a way that f is continuous function on its domain. f(x)= { (√x+a)+1 if -a ≤x ≤ 0 2x^2+3 if 0 ≤ x ≤ 1 (x+b)^2+1 if x>1

*September 25, 2016*

**was not in class bio/ math**

Preparing a Solution: A. Calculate the amount of methylene blue chloride (MW = 319.8 g/mol) needed to make 50 ml of a 10 mM stock solution. (Show calculations below) B. If you wanted to then dilute the solution from Part A to a final concentration of 0.1mM (in 50 ml total ...

*September 20, 2016*

**math**

translate the following sentence into an equation: The product of 9 and four less than n is 27 is is 9(n-4)=27 or 9n-4 = 27

*September 13, 2016*

**Chemistry**

Do you think the copper and zinc underwent a physical change or a chemical change?

*September 7, 2016*

**Algebra 1**

you have $50 in your bank account and you deposit $20 per week. Write an equation for the total amount of money you have in your account after x weeks.

*September 7, 2016*

**Math**

CLIMATOLOGIST Each year a tree is alive,it adds a layer of growth,called a tree ring,between its core and its bark. A climatologist measures the width of tree rings of a particular tree for different years: YEAR: 1900:1910:1920:1930:1940 Width of ring:14/25:29/50:53/100:13/20:...

*September 6, 2016*

**Texas History**

Both answers is wrong it's C if you want to be correct just pick it it will be right becauseI chose D and it said it was wrong as well with A and B.

*August 26, 2016*

**English**

Revise the following sentence so that ACTIONS name KEY VERBS. 1. Our discussion was lively and fun

*August 25, 2016*

**Health**

Which of the answer is correct

*August 18, 2016*

**chemistry**

A major component of gasoline is octane C8H18. When octane is burned in air, it chemically reacts with oxygen gas O2 to produce carbon dioxide CO2 and water H2O. What mass of octane is consumed by the reaction of 8.8g of oxygen gas? Round your answer to 2 significant digits.

*August 9, 2016*

**Math**

composite number: positive integer that isn't a prime number Less than 10 + greater than 6 + even: 8 - Factors: 1,2,4,8 -- composite Answer:8

*August 3, 2016*

**calc **

a parallelogram has an area of 150 cm^2. the side lengths are 80 cm and 40 cm what are the measures of the angles

*July 15, 2016*

**calculus **

A door is opened by pushing inward explain in terms of torque why this is most easily accomplished when pushing at right angles to the door as far as possible from the hinge side of the door?

*July 15, 2016*

**calc **

a wrench is rotated with torque of magnitude 175 N (M). the force is applied 45 cm from the pivot point at an angle of 48 degrees. what is the magnitude of the force, to one decimal place?

*July 15, 2016*

**calc**

Would k(a-b) x (a x c) -a +( b x c) be a scaler, vector or meaningless? (these are all vectors besides k)?

*July 15, 2016*

**Math**

Thank yoU!

*July 14, 2016*

**Math **

Mr.Adams had a coin collection including only nickels, dimes, and quarters He had twice as many dimes as nickels and half as many quarters as he had nickels. If the total face value of his collection was $300.00, how many quarters did the collection contain? A) 75 B) 100 C) ...

*July 14, 2016*

**Calc. **

Determine the value and value for each of the following: a) 2(3,y )-5(x,2)= (6,-4 )

*July 8, 2016*

**Calc. **

Find the angle between the vectors ⃗⃗u (-1,4,2 ) and ⃗v (-2,5,1 )

*July 8, 2016*

**Sciencr**

Why is a cool basement damp, in terms of humidity? I know that when you increase temperature and relative humidity decreases but I don't get how this fits? It's a closed environment so maybe there is condensation?

*July 2, 2016*

**algebra**

Yes it can be whatever you want between that given range. For example, if the slope was -0.2, (or -1/5) then, your line would go down from left to right (because it's negative) and move down 1 every time you move 5 to the right (m= rise/run) Hope that helps!

*June 13, 2016*

**Math**

Marie traveled to work (7km) in 25 minutes. What was her speed? I got 16.8km/h but my teacher said it's 28km/h and I have no idea how he got that. Also, how do you calculate average speed when there's more than one speed? (this is just for the next question)

*June 13, 2016*

**math**

First, I would put all the times to one unit. (I'm going to use minutes because I don't like working with decimals.) 1 hour: 60 minutes 1 day: 60 minutes times 24 (hours in a day) = 1440 minutes Now set up proportions: 150 people/1 minute = x people/60 minutes cross ...

*June 13, 2016*

**algebra**

a math exam is marked out of 120. draw a conversion graph to change the following marks to percentages. a_80 b_110 c_54 d_72

*June 6, 2016*

**algebra**

long-distance calls from New York to Harare are priced at 85 cents/min off peak and $1.20/min at peak times. a_ draw, on the same exes, conversion graphs for the two different rates. b_ from your graph estimate the cost of an 8 minute call made off peak. c_ estimate the cost ...

*June 6, 2016*

**algebra**

long-distance calls from new york to harare are priced at 85 cents/min off peak and $1.20/min at peak times. a_ draw, on the same axes conversion graphs for the two different rates. b_ from your graph estimate the cost of an 8 minute call made off peak. c_ estimate the cost of...

*June 6, 2016*

**Calculus**

I should probably specify that I got the area by integrating y^(-1/2) - (-y^(-1/2)) with my calculator on the interval [1,3] Sorry!

*May 24, 2016*

**Calculus**

Find the area of the region bounded by the curves y = x^(-1/2), y = x^(–2), y = 1, and y = 3. a) (1/2)(3)^1/2 + (4/3) b) 2*(3)^1/2 - (8/3) c) (1/2)(3)^1/2 - (32/3) d) 2*(3)^1/2 - (32/3) e) (8/3) - 2*(3)^1/2 So one thing that is throwing me off on this question is that I ...

*May 24, 2016*

**trigonometry**

Verify that sec(θ)/csc(θ)-cot(θ) - sec(θ)/csc(θ)-cot(θ) = 2csc(θ) is an identity. can some help me through this? thank you!

*May 24, 2016*

**trigonometry**

25. simplify: sin^2 ø/1- cos ø please help? thank you!

*May 20, 2016*

**math**

i don't have any work to show you... i don't get it

*May 15, 2016*

**math**

You want to cover a trapezoidal box with paper. You have a sheet of paper that is 1m by 500cm. What is the size box that can be made with minimal wastage? plz plz plz help me with this.. i don't understand how to do this

*May 15, 2016*

**Algebra**

You want to cover a trapezoidal box with paper. You have a sheet of paper that is 1m by 500cm. What is the size box that can be made with minimal wastage?

*May 15, 2016*

**Maths**

the total answer will be 437 +248 6 8 5

*May 15, 2016*

**Maths**

437 +248 do the math...

*May 15, 2016*

**Maths**

okay, and does the 4 at the bottom go under 3 and the 8 go under 7?

*May 15, 2016*

**Maths**

Does the 2 go under 4 or 3?

*May 15, 2016*

**math**

9. solve |4x + 3| = 9 + 2x and check for extraneous solutions. the first answer I got was: |4x +3| = 9 + 2x |4x| = 6 + 2x 2x = 6 x = 3 can someone help me find the other answer? thank you!

*May 12, 2016*

**math**

8. The half-life of a certain radioactive material is 71 hours. An initial amount of the material has a mass of 722 kg. Write an exponential function that models the decay of this material. Find how much radioactive material remains after 17 hours. Round your answer to the ...

*May 11, 2016*

**math**

6. The half-life of a certain radioactive material is 32 days. An initial amount of the material has a mass of 361 kg. Write an exponential function that models the decay of this material. Find how much radioactive material remains after 5 days. Round your answer to the ...

*May 11, 2016*

**Math **

A tank measures 30 can by 60cm by 50cm. What is the height of water in the tank when 60000 ml of water are poured into it?

*May 10, 2016*

**math**

O MY GOODNESS I UNDERSTAND NOW THANK YOU SO MUCH

*May 10, 2016*

**math**

14. Let f(x) = -2x - 7 and g(x) = -4x + 3. Find (f o g)(-5) A)23 B)-53 C)-9 D)3 please help!!

*May 10, 2016*

**math**

17. Let f(x) = x2 + 6 and g(x) = x+8/x . Find ( g o f)( -7) A)384/7 B)295/49 C)-57/7 D)63/55 could someone please help?

*May 10, 2016*

**math**

18. For the function f(x) = x2 -12, find (f o f-1)(4). A)4 B)10 C)6 D)0 help please?

*May 10, 2016*

**Math**

Yesterday kate and her cousin robert went out for a movie there they spent $50 in total robert spent $10 more than kate how much did kate spend?

*May 9, 2016*

**Chemistry **

how many grams of AlCl3 is produced if 15.5 grams of Al are reacted with excess Cl2 gas? 2Al + 3Cl2 > 2AlCl3

*May 9, 2016*

**math**

sorry, I meant A or B, because I am "sure" that there is a remainder from looking at the equation. I just needed someone to help go through the equation.

*May 6, 2016*

**math**

Divide -3x^3 - 2x^2 - x - 2 by x – 2. A. -3x2 - 8x - 17, R –36 B. -3x2 + 4x + 15, R 32 C. -3x2 + 4x + 15 D. -3x2 - 8x - 17 I'm sure it's either B or C, can someone help?

*May 6, 2016*

**math**

Is the relation a function? 4 -> 8 7 -> 11 10 -> 14 12 -> 10 A. yes B. no

*May 4, 2016*

**Geometric Sequence**

The colour of some clothing fades overtime when washed. Suppose a pair of jeansfades by 5% with each washing. To the nearest wash, how many washes would it take so that only 25% of the original colour remains in the jeans? 1. first term = 2. r = 3. tn = 4. n = I know that tn ...

*May 4, 2016*

**math**

The distance between town A and town B was 210 km. At 9:20 pm, a bus set off from town A to town B and a car from town B to town A. The average speed of the bus was 60 km/h, and the average speed of the car was 80 km/h. a) Calculate the time at which the car passed the bus. b...

*April 28, 2016*

**math**

Ava made 100 paper cranes, and Brittany made 3/4 of paper cranes Ava made. Ava gave 9/20 of her paper cranes to Brittany. Then, Brittany gave 1/4 of her paper cranes to Ava. How many more cranes did Brittany have than Ava in the end?

*April 28, 2016*

**Physics**

a cube slides down a frictionless incline as shown and inelastically strikes a cube at the battom of the incline that's 1/2 (one-half) it's mass. The coeff. of restitution between the two masses is 0.7. If incline is 30 cm high and table is 90cm off floor, at what ...

*April 27, 2016*

**physics**

a cube slides down a frictionless incline as shown and inelastically strikes a cube at the battom of the incline that's 1/2 (one-half) it's mass. The coeff. of restitution between the two masses is 0.7. If incline is 30 cm high and table is 90cm off floor, at what ...

*April 26, 2016*

**Math **

A person plans to invest a total of $9000 in an account that pays 3% annual interest and another account which pays 8% annual interest. How much should be invested in each account so that the total interest for one year will be $580.

*April 25, 2016*

**math**

the power (P) generated in a electrical circuit is proportional to the square of the current ( L amps) . when the power is 108, the current is 6 amps. a_ write down the relationship between P,L and the constant of variation k . b_ calculate the value of k c_ calculate the ...

*April 24, 2016*

**math**

the length ( L cm) of an edge of a cube is proportional to the cube root of its mass ( M grams).It is known that if L= 15, then M=125. let K be the constant of variation. CALCULATE THE VALUE OF K

*April 23, 2016*

**Physics**

Blood flows in an aorta of radius 4.62mm at 35.0cm/s. Calculate the volume flow rate. Although the cross-sectional area of a capillary is much smaller than that of the aorta, there are many capillaries, so their total cross-sectional area is much larger. If all the blood from ...

*April 22, 2016*

**Physics**

Thank you!

*April 22, 2016*

**Physics**

I keep getting .154

*April 22, 2016*

**Physics**

Thank you so much! And What distance, d, from the edge of the table does the block hit the floor?

*April 22, 2016*

**Physics**

A 0.294-kg box is placed in contact with a spring of stiffness 3.792×102 N/m. The spring is compressed 1.42×10-1 m from its unstrained length. The spring is then released, the block slides across a frictionless tabletop, and it flies through the air. The tabletop ...

*April 22, 2016*

**Chemistry**

The pH of human blood needs to be between 7.35 and 7.45. You want to prepare a buffer solution that gives a pH of 7.40. You decide to use a sodium phosphate buffer: the acid is H2PO− 4 and the conjugate base is HPO2− 4 . You want the concentration of the acid to be...

*April 22, 2016*

**Math**

Thank you£¡

*April 22, 2016*

**Math**

I don¡¯t know how to slove this problem can someone help me£¿ The shorter leg of a 30¡ã60¡ã90¡ãtriangle is 2.5 feet long.Find the perimeter.

*April 22, 2016*

**Physics**

Consider a metal rod that is 1.42 m in length at a temperature of 14.4°C. The coefficient of linear expansion is 5.22×10-5°C-1. What is the change in length of the rod as temperature increases from 14.4°C to 52.0°C.

*April 21, 2016*

**Language arts**

1.C 2.D 3.A 4.D

*April 20, 2016*

**Physics**

The volume flow rate in an artery supplying the brain is 4.59E-6 m3/s. If the radius of the artery is 5.33 mm, determine the average blood speed.

*April 20, 2016*

**Physics**

A block of mass M=0.525kg is floating stationary in a beaker of water. A string connected to the bottom of the beaker holds the block in place. The tension in the string is 7.10 N. The bottom of the block is floating a distance h=1.66cm above the bottom of the beaker. What is ...

*April 20, 2016*

**Chemistry**

I'm sorry the full question was: 1. If the initial H2PO− 4 concentration is 0.0100 M, what is the initial concentration of HPO2− 4 that will give a pH of 7.40? 2. What is the maximum molarity of acid that this buffer can neutralize without the pH dropping below...

*April 19, 2016*

**Chemistry**

The pH of human blood needs to be between 7.35 and 7.45. You want to prepare a buffer solution that gives a pH of 7.40. You decide to use a sodium phosphate buffer: the acid is H2PO−4 and the conjugate base is HPO2− 4. You want the concentration of the acid to be 0...

*April 19, 2016*

**Math**

A high school has 438 students with about the same number of males and females. Describe a simulation to predict how many of the first 50 students who leave school at the end of the day are female.

*April 19, 2016*

**Math**

Talia tossed a penny many times. she got 40 heads and 60 tails. she said the experimental probability of getting heads was 40 over 60. Explain and correct her error.

*April 19, 2016*

**math**

Shoot. I meant to say how to write this equation in standard form: y=(x+1)(x-1)(x-1)

*April 18, 2016*

**Precalculus**

A population of bacteria has exponential growth and will double after 10 hours. Find the growth rate to the nearest hundredth.

*April 13, 2016*

**Physics**

A spring loaded ballistic pendulum gun requires an increasing force to load. When loading a ball of mass 0.054 kg, the spring is compressed 7.00 cm, the gun is fully loaded, and the force required is 70.0 N. a) Calculate the work required to load the gun. b) Calculate the ...

*April 12, 2016*

**Physics**

A pendulum clock can be approximated as a simple pendulum of length 1.03 m and keeps accurate time at a location where g = 9.82 m/s2. In a location where g = 9.77 m/s2, what must be the new length of the pendulum, such that the clock continues to keep accurate time (that is, ...

*April 12, 2016*

**Stats**

{Exercise 7.11} The following data are from a simple random sample. 3, 8, 11, 6, 11, 15 What is the point estimate of the population mean? 9 What is the point estimate of the population standard deviation (to 1 decimal)?

*April 8, 2016*

**Geometry**

a jewlery box in the shape of a rectangle prism has a volume of 90in.3 and a height of 2 1/2 in, What are possible demensions for the length and width of base

*April 6, 2016*

**Physics**

A horizontal circular platform (m = 110.1 kg, r = 3.21m) rotates about a frictionless vertical axle. A student (m = 98.3kg) walks slowly from the rim of the platform toward the center. The angular velocity, omega, of the system is 3.9 rad/s when the student is at the rim. Find...

*April 6, 2016*

**chemistry**

If 5.40 kcal of heat is added to 1.00 kg of water at 100⁰C, how much steam at 100⁰C is produced? Show all calculations leading to an answer. Please help?

*April 6, 2016*

**chemistry**

You have two sealed jars of water at the same temperature. In the first jar there is a large amount of water. In the second jar there is a small amount of water. Using 3 -4 sentences explain how the vapor pressure of water in the first jar compares with the vapor pressure of ...

*April 6, 2016*

**Math**

Which hand has covered more distance from the 12 on a clock, the minute hand at 4:00 or the second hand at 15 seconds past? Write a fraction inequality to support your answer.

*April 5, 2016*

**Trig**

Find the exact values of sec(x)=7. I know that cos(x)=1/7. I know that sin(x)= sqrt(1-91/4900). I know that tan(x)=1. I know how to do the problem but I'm not really sure why, and I'd like to know. I got 4sqrt(3). Please help!

*April 1, 2016*

**Calculus**

I got the second answer. Still confused on the first one.

*April 1, 2016*

**Calculus**

Find the exact value of cot(arcsin(12/13)) and cos(arcsin(1.7/2)) I know that cos(arcsin(x))=sin(arccos(x))=sqrt(1-x^2). I'm having more difficulty with the first one. Please help! Thank you

*April 1, 2016*

**Calculus**

How do I tell the difference between a non conic function and a conic function by looking at an equation?

*March 31, 2016*

**chemistry**

A gas occupies 5.65 L at 808 torr and 17◦C. What volume will it fill if the pressure is changed to 730 torr and the temperature is raised to 51◦C?

*March 30, 2016*

**Algebra**

Find two consecutive even integers such that the square of the lesser integer increased by twice the greater integer is 364.

*March 30, 2016*

**Physics**

Just saw your reply, bobpursley. I will show you my work in a few minutes. Thank you

*March 30, 2016*

**Physics**

I got a, but can't figure out the rest of the questions. Please help! Thank you

*March 30, 2016*

**Physics**

A high-speed sander has a disk 5.70 cm in radius that rotates about its axis at a constant rate of 1120 revolutions per minute. a.) Determine the angular speed of the disk in radians per second. b.) Determine the linear speed of a point 2.40 cm from the disk's center. c.) ...

*March 30, 2016*

**Physics**

How do you turn revolutions into radians? Please help!

*March 30, 2016*

**Physics**

A wheel has a radius of 5.22 m. a.) How far (path length) does a point on the circumference travel if the wheel is rotated through an angle of 34.3°? b.) How far does a point on the circumference travel if the wheel is rotated through an angle of 34.3 rad? c.) How far does...

*March 30, 2016*

**Physics**

A pulsar is a rapidly rotating neutron star that continuously emits a beam of radio waves in a searchlight manner. Each time the pulsar makes one revolution, the rotating beam sweeps across the earth, and the earth receives a pulse of radio waves. For one particular pulsar, ...

*March 29, 2016*

**Physics**

A block of mass 0.61kg starts from rest at point A and slides down a frictionless hill of height h. At the bottom of the hill it slides across a horizontal piece of track where the coefficient of kinetic friction is 0.40. This section (from points B to C) is 4.73m in length. ...

*March 29, 2016*