Saturday

July 4, 2015

July 4, 2015

Total # Posts: 1,161

**chemistry **

who was the first scientist to identify a nuclear bombardment reaction?
*February 8, 2012*

**Physics!! Help!!!!!**

. A neutral conducting sphere contains a spherical cavity. A point charge +q is located at the |center of the cavity. A. What is the total surface charge on the interior surface of the conductor? B. What is the total charge on the exterior surface of the conductor?
*February 3, 2012*

**math**

the top will have a piece of marble 20 1/2 by 22 bordered by 3 1/4 inches of wood on all four sides. Give the overall dimension of the table top
*February 2, 2012*

**physics**

The angle between the polarizer transmission axis and the plane of polarization of the incoming light is 30 +/- 2 deg. If the incident light intensity Io is 100 W/cm2 what would be the intensity I after the light is transmitted through the polarizer? What would be the percent ...
*January 27, 2012*

**Precalculus**

Consider the equation 7sin^2x - (4sin2^x)/cosx = -1 a) Put the equation in standard quadratic trig equation form. Why is it 7sin^2x - 8sinx + 1 =0?
*January 27, 2012*

**Precalculus**

Which of the following is a solution for the equation 1/485tan^2x = 0? a) pi b) pi/2 c) 485pi d) no solution Which of the following is NOT a solution to the equation 4sin^2x = 1 for 0≤x≤2pi? a) 30 degrees b) 210 degrees c) 150 degrees d) 120 degrees?
*January 27, 2012*

**Precalculus**

Solve the equation (x+3)(x-3) = -9. What are the solutions to the equation if you replace x first with sinx and then with cosx, where 0≤x≤2pi?
*January 26, 2012*

**Precalculus**

Thank you!
*January 26, 2012*

**Precalculus**

Thank you~ May I know how you got 150 degrees? I am so confused when finding the reference angles, whether to subtract or add the degrees.
*January 26, 2012*

**Precalculus**

Sorry, I meant 2sinx - cos^2x = sin^2x for 0 ≤ x ≤ 2π 2sinx - cos^2x = sin^2x Do I change the left side to 2sinxcosx - cos^2x = sin^2x
*January 26, 2012*

**Precalculus**

Determine the solutions to the equation 2sinx − cos2x = sin2x for 0 ≤ x ≤ 2π . How do I start this question?
*January 26, 2012*

**Math**

How can I figure out what the line segment of radical, or Sq root of 17 looks like?
*January 18, 2012*

**Physic**

A cheetah can accelerate at a rate of 8.0 M/S^2. Assuming it starts from rest, what will its velocity be after 3.5 SECONDS?
*January 14, 2012*

**math**

a certain antibiotic redues the number of bacteria in your body by 10% each dse, if 4 doses of the antibiotic are taken, what percent of the original bacterial population is left
*January 3, 2012*

**math**

sam invested $5000 in a GIC earning 8% compound interest per year, the interest gets added to the amount invested, so the next year sam gets the interest on the interest already earned , as well as on te original amoun, how much will sam's investment be worth at the end of...
*January 3, 2012*

**math**

a student plants a seed, after the speed sprouts the student monitors the growth of the plant by measuring its height every week, the height after each of the first tree wees was 7mm , 20mm, and 33mm, respectively, if this pattern of growth continuesinwhat week will the plant ...
*January 3, 2012*

**math**

determine the 100th term of the arithmetic sequence with t7=465 and t13=219
*January 3, 2012*

**world religions**

In class I got this question any help would be great!! I have no clue how to answer it. If Jesus were human, what does this mean for Christianity and Judaism
*December 31, 2011*

**chemistry**

10 J
*December 30, 2011*

**science**

describe the path that oxygen follows through the human body to reach muscle tissue and describe the path carbon dioxide follows from inside the cell to the outside envrionment
*December 29, 2011*

**science**

what 3 anatomical factors influence a persons vo2max and what 3 internal physiological factors influence a persons vo2max
*December 29, 2011*

**math**

A catering company has 15 customer orders during its first month, for each month afterward, the comopany has double the number of orders than the previous month. How many orders in total did the company fill at the end of its first year ?
*December 17, 2011*

**math**

a ball is dropped from a height of 3m and bounces on the ground . At the top of each bounce, the ball eaches 60% of its previous height. Calculate the total distance travelled by the ball when it hits the ground for the fifth time
*December 17, 2011*

**Math**

The 13th termof an arithmetic sequence is 61 and the 20th term of the squence is 82. Calculate the sum of the first 25 terms of the sequence
*December 17, 2011*

**Math**

the 12th term in a geometric sequence is 49, and the 14th term is 2401 . Find the 15th term
*December 17, 2011*

**algebra**

The first 1/5 of a mile is $1.50. For every additional 1/5 of a mile is 25 cents. If Marc has $3.75, at least how far can he go? P.S. I need an inequality.
*December 14, 2011*

**physics 2B**

This ties in with chemistry actually. They give you Temperature, Pressure, and Volume. Convert temperature to Kelvins (add 273) and convert your volume to Liters. Use R constant 0.0821. Plug into the ideal gas law of PV=nRT and solve for the moles of the He atom (thats n). ...
*December 10, 2011*

**Chemistry**

Thanks so much! That makes alot more sense now. The figures really helped out.
*December 10, 2011*

**Chemistry**

Not to mention the conversions! But thanks a million. :) I got a range of an average of 0.064 nm to 0.45 nm. Considering concept wise though, do the units of nm make sense for an atoms diameter? Thats not visible right?
*December 10, 2011*

**Chemistry**

True or False: The diameter of most atoms will be between 0.05 nm and 0.3 nm. I think its false (I don't think there even is an average diameter for atoms...), but I can't find any reliable sources to back up my hunch. Help please...
*December 10, 2011*

**math**

Matthew is riding a ferris wheel at a constant speed of 10km/h. The boarding height for the wheel is 1m, and the wheel has a radius of 7m. What is the equation for the function that describes Matthews height in the terms of time, assuming Matthew starts at the highest point on...
*December 8, 2011*

**Math**

The diameter of a car's tire is 60cm . While the car is being driven , the tire picks up a nail .How high above the ground is the nail after the car has travelled 1km
*December 8, 2011*

**Biology**

explain the process of adaptive radiation, and how are reproductive barriers important to speciation
*December 8, 2011*

**World religions**

For this project for school we have to represent the noble eightfold path ( right view) to canadian society , but i am so stuck , i dont really know anything that would make sense, any help would be great
*December 3, 2011*

**chemistry**

Calculate the pH of each of the following solutions. (a) 0.300 M propanoic acid (HC3H5O2, Ka = 1.3 10-5) (b) 0.300 M sodium propanoate (NaC3H5O2) (c) pure H2O (d) 0.300 M HC3H5O2 and 0.300 M NaC3H5O2
*December 2, 2011*

**chemistry**

The Ksp for silver sulfate (Ag2SO4) is 1.2 10-5. Calculate the solubility of silver sulfate in each of the following. A)water B)0.14 M AgNO3 C)0.33 M K2SO4 the answer in mol/L
*December 2, 2011*

**math**

how do u do lost digits?? my son has to do this for homework and we are both stuck on how to do this.
*November 30, 2011*

**Statistics**

The average hourly wage of employees in a large nationwide industry is $12.96. Assume the variable is normally distributed, with a standard deviation of $4.46. In a randomly selected sample of 10,000 such employees, how many of them (correct to the nearest hundred) would you ...
*November 28, 2011*

**statistics**

570 people were in a survey and 124 people said yes. What proportion of people said yes to 1 d.p
*November 24, 2011*

**chemistry**

Calculate the pH of a 0.063 M (C2H5)2NH solution (Kb = 1.3 10-3).
*November 24, 2011*

**Chemistry**

Calculate the molar heat of neutralization in kJ/mol of the reaction between HA and BOH given the following information: The temperature change equals 8C, 50 mL of 1 M concentration of Acid 50 mL of 1 M concentration of Base Heat capacity of the calorimeter is 6.5 J/C. ...
*November 20, 2011*

**math**

prove these identies sin^2+tan^2=sec^2-cos^2 sin^2 sec^2 +sin^2=tan^2+sin^2
*November 18, 2011*

**math**

An urn contains 5 red marbles, 4 blue marbles, and 3 green marbles. A marble is selected at random and then, without replacing the first marble, a second marble is selected at random. What is the probability of selecting a green marble and then a red marble?
*November 16, 2011*

**English**

What are the differences between the characters Johnny and dally, in the story The Outsiders by S.E. Hinton?
*November 14, 2011*

**english**

what does this mean? how can i summarize it ?? "we acquire language not just because we are taught it, but because we are born with the principles of language. They're in our genes. We have language because of nature, not just nurture"
*November 14, 2011*

**math **

Let R be a commutative ring in with a^2=a for every element a. Show that a+a=0 for all a in R
*November 13, 2011*

**MATH--PLEASE HELP**

Let W be the set of all continuous fuctions from the set of real numbers R to R. For f, g in W define f+g by (f+g)(x)=f(x)+g(x) and (f*g)=f(x)g(x). Verify that W is a commutative ring. Does W have unity? Why or why not?
*November 13, 2011*

**algebra**

7 * sqrt 20 = 7 * sqrt 5 * sqrt 4 = 7* sqrt5 * 2 = 14sqrt5 so (14sqrt5) - (8sqrt5)= 6sqrt5
*November 13, 2011*

**Biology**

In guinea pigs, gene B is for black, b is for white the heterozygote is a mixture, called agouti. ( sex linked and non dominant) , a litter consists of 5 agouti females and 6 black males , if the parents of this litter had more offspring , what other phenotypes would you ...
*October 26, 2011*

**Biology**

In man, muscular dustrophy , is inherited as a sex linked recessive , a couple , both of whom are normal, have five children, three boys and two girls , the oldest boy is beginning to show symptoms of the disease, what could you tell them about the chances of their children ...
*October 26, 2011*

**Biology**

Suppose that a clolur blind man has parents with normal vision. Would all his sons be colour-blind ? Was his mother a carrier ? would all his daughters be carriers
*October 26, 2011*

**math**

determine the value of k such that g(x)=3x+k intersects the quadratic function f(x)=2x^2-5x+3 at exactly one point determine the value(s) of k such that the linear function g(x)=4x+k does not intersect the parabola f(x)=-3x^2-x+4
*October 24, 2011*

**math**

Determine the equation of the inverese of the quadratic function f(x)=x^2-4x+3
*October 22, 2011*

**math**

The sum of two numbers is 16 . What is the largest possible product between these numbers
*October 22, 2011*

**math**

Express each function in standard form f(x)=-3(x-2)^2+5 f(x)=2(x+4)(x-6)
*October 22, 2011*

**math**

For a fixed element 'a' of a ring R, prove that the set {x exists in R such that ax=0)is a subring of R.
*October 20, 2011*

**History**

Did the Elastic Clause justify acts such as Hamilton's excise tax and the Bank of the United States or Jefferson's Louisiana Purchase?
*October 19, 2011*

**Math( help please ! )**

The profit p(x) of a cosmetics company , in thousands of dollars,is given by p(x)=-5x^2+400x-2550, where x is the amount spent on advertising , in thousands of dollars a) determine the max profit the company can make b)Determine the amount spent on advertising that will result...
*October 17, 2011*

**Math( help please ! )**

thank you so much
*October 17, 2011*

**Math( help please ! )**

The height of a ball thrown vertically upward from a rooftop is modelled by y=-5t^2+20t+50 , where h(t) is the ball's height above the ground , in meters , at time t seconds after the throw a) Determine the max height of the ball b) how long does it take for the ball to ...
*October 17, 2011*

**Math( help please ! )**

Determine the maximum of or the minimum value of y=2x^2+12x
*October 17, 2011*

**Biology **

In drosophila , short wings , and black colour are reccessive traits.long wings and grey colour are dominant. show the cross results between a short winged , heterozygous grey fly and a heterzygous long winged grey fly
*October 17, 2011*

**Biology( HELP PLEASE)**

thank you so much
*October 14, 2011*

**precalcus**

a positive angle less than 2 pi their is a coterminal 17 pi/4
*October 13, 2011*

**Math**

the height of a rocket above the ground is modelled by the quadratic function h(t)=-4t^2+32t a) how long will the rocket be in the air ? how do you know? b) what is the maximum height that the rocket will reach ?
*October 13, 2011*

**physics**

According to the above reference the answer would be 45cm yes? - which doesn't make sense because there is only 20cm of board from the end of the table. And i'm not exactly sure where the 25cm came from? Can someone please expand on this answer?
*October 12, 2011*

**Math**

50x^2-72
*October 10, 2011*

**Mathh !!!!! Help please !!!**

i tried these quesions so many times , but i just cant get he right answer ! 1.) 4(2-a)^2-81 2.) -(x-y)^3 3.)3x^2-27(2-x)^2 4.) 9(y-1)^2-25
*October 2, 2011*

**Math help please**

i tried these quesions so manytimes , but i just cant get he rigt answer ! 1.) 4(2-a)^2-81 2.) -(x-y)^3 3.)3x^2-27(2-x)^2 4.) 9(y-1)^2-25
*October 2, 2011*

**Math**

Factor 1. a^4-16 2. (m-n)^2-(2m+3n)^2 3.2x^4y^4-6x^5y^3+8x^3y 4.12m^2n^3+18m^3n^2
*October 2, 2011*

**Math**

simplify 1. (2x^4-3x^2-6)+(6x^4-x^3+4x^2+5) 2. -7x(x^2+x-1)-3x(2x^2-5x+6) 3. -2x[ 5x-(2x-7)]+6x[3x-(1+2x)]
*October 2, 2011*

**Math**

expand and simplify 1. -(y^2-4y+7)(3y^2-5y-3) 2.2(a+b^3
*October 2, 2011*

**math**

expand and simplify 1.(x^2-3x+4)(-x^2+3x-4) 2.3(2x-5)-9(4x-5)
*October 2, 2011*

**Math**

Factor 1. 8a^2-2ab-21b^2 2. 6m^2-90m+324 3.5x(2-x)+4x(2x-5)-(3x-4) 4. 9(y-1)^2-25 5. 3x^2-27(2-x)^2
*October 2, 2011*

**Math**

Expand and simplify 1.(9a-3)^2 2.(x^2+2x-1)^2 3. 2(3a+4)(a-6)-(3-a)^2+4(5-a)
*October 2, 2011*

**math**

If f(x) = (x-4) (x+3) , determine the x-intercept of each function a)y=f(x) b) y=-2f(x) c) y=(-(x+1)) thanks for the help !!!!!!
*September 25, 2011*

**math**

a function f(x)has doamin {xeR/x>-4} and range {yeR/y<-1) . Determine the domain and range for each function. a) y=2f(x) b) y=f(-x) c) y=3f(x+1)+4 d) y=-2f(-x+5)+1 thanks for the help !!!
*September 25, 2011*

**Math !!!!!**

a function f(x)has doamin {xeR/x>-4} and range {yeR/y<-1) . Determine the domain and range for each function. a) y=2f(x) b) y=f(-x) c) y=3f(x+1)+4 d) y=-2f(-x+5)+1 thanks for the help !!!
*September 24, 2011*

**Math**

If f(x) = (x-4) (x+3) , determine the x-intercept of each function a)y=f(x) b) y=-2f(x) c) y=(-(x+1)) thanks for the help !!!!!!
*September 24, 2011*

**math **

for h(x)=5-4x, determine the input for x when the output of h(x) is -11 i have tried to answer this question so many times , but i cant figure it out
*September 22, 2011*

**math **

a teacher asked her students to think of a number, multiply by 5, and subtract the product from 20 , then she asked them to multiply the resulting difference by the number they first thougt of a) use function notation to express the final answer in terms of the orginal number ...
*September 22, 2011*

**Math**

for h(x)=5-4x, determine the input for x when the output of h(x) is -11
*September 22, 2011*

**Math**

a teacher asked her students to think of a number, multiply by 5, and subtract the product from 20 , then she asked them to multiply the resulting difference by the number they first thougt of a) use function notation to express the final answer in terms of the orginal number...
*September 22, 2011*

**math**

for h(x)=5-4x, determine the input for x when the output of h(x) is -11
*September 21, 2011*

**math **

a teacher asked her students to think of a number, multiply by 5, and subtract the product from 20 , then she asked them to multiply the resulting difference by the number they first thougt of a) use function notation to express the final answer in terms of the orginal number ...
*September 21, 2011*

**math**

sorry for the delay.. I don't understand. I do understand that a new 1000 is not needed because once added, it's still 1000 but as as far as the rest, I don't understand. Trying to help my daughter with her math homework!
*September 20, 2011*

**math**

sorry for the delay.. I don't understand. I do understand that a new 1000 is not needed because once added, it's still 1000 but as as far as the rest, I don't understand. Trying to help my daughter with her math homeworl!
*September 20, 2011*

**math**

write each addition vertically.decide which new groups you will make.then,add to see if you were correct. 256+1273___________ a new ten?____________ a new hundred?_________ a new thousand?____________ need answers and please explain
*September 20, 2011*

**visual basic 2010**

I am totally lost with arrays. I have a program that needs to store users entries(first & last name...etc) in 2 different arrays. The summary button then loops thru each array and outputs their contents to the immediate window. Then the exit button displays the number of items...
*September 18, 2011*

**language arts**

Some visitors to the park enjoy rock climbing others prefer kayaking.
*September 17, 2011*

**Physics**

You compress air saturated with water vapor at 24°C and atmospheric pressure (101.325 kPa) until the total pressure is doubled and the temperature is 36°C. What is the final pressure of the water vapor?
*September 13, 2011*

**Physics**

The V.A-3 had an average speed of 96 km/h. Its momentum at this speed was 4.8 x 10(4)kg x m/s. What was the mass of the V.A-3?
*September 12, 2011*

**algebra**

60 = (66+72+90+49+59+x)/6 Solve for x.
*September 5, 2011*

**Algebra**

60 = (66+72+90+49+59+x)/6 Solve for x.
*September 5, 2011*

**Algebra**

Thank you, I got that but I don't know how to solve for x
*September 5, 2011*

**Algebra**

To pass a course you need an average score of 60 or more. If your scores are 66, 72, 90, 49, and 59, find the minimum score that you can get on the 6th and last exam to pass the course.
*September 5, 2011*

**PHYSICS**

A piece of wood is floating at the surface of some water as illustrated (the diagram is not to scale). The wood has a circular cross section and a height h = 4.0 cm. The density of water is 1.00 g/cm3. The distance y from the surface of the water to the bottom of the wood is 3...
*August 9, 2011*

**PHYSICS**

A 50cm long hollow glass cylinder is open at both ends and is suspended in air. A source o sound that produces a pure frequency is placed close to one end of the tube. The frequency of the sound is slowly increased from a very low value. The tube is first observed to resonate ...
*August 9, 2011*

**PHYSICS HELP**

A solid cylinder has an area of 10cm2 and a height of 1.0 m. The cylinder is composed of two different materials with mass densities of 2000 kg/m3 and 1500 kg/m3. If each of the two materials occupies an equal volume, what is the mass of the cylinder? Question 3 options: A) 3....
*August 8, 2011*

**PHYSICS - HELP**

I NEED HELP ON C THROUGH F. THANK YOU A spring id vertically, as shown below, and a 500g mass is hung from its lower end. The EQUILIBRIUM extension of the spring is observed to be 10.0cm. (1) What is the spring constant of the spring? ANSWER: 49N/m (B) If the is pulled down by...
*August 7, 2011*