Monday

April 27, 2015

April 27, 2015

Total # Posts: 609

**Pre-calc**

There exist constants a, b, c, and d such that(sin x)^7 = asin 7x + bsin 5x + csin 3x + dsin x for all angles x. Find d. I tried rewriting them in the exponential form, but it becomes ugly as there are many negative cosines and divisions of i. Help?
*April 7, 2015*

**Physics**

A skateboarder approaches the circular hill with a velocity of 8.0 m/s at point B. The angle formed between the lines that join point AO and BO is 20 degrees. a) what is her speed at the top of the hill(Point A) if she coasts up to this point? b) what min speed must she have ...
*April 7, 2015*

**chemistry**

why doesnt the radius ratio rule work for TlCl3??? the division would be the radius of the cation / radius of the anion. For Tl3+ and Cl-...88pm/181pm = .49 which would correspond to a 'zinc blende' crystal structure and not a CsCl type crystal as the rest of the ...
*March 7, 2015*

**science**

I would say it is 0 because work is the a function of Force and horizontal displacement.
*March 7, 2015*

**math**

A cyclist covers his outward journey downhill at 24mph. His return journey, over exactly the same distance uphill, is covered at only 12mph. What is the cyclist's average speed over the entire journey?
*March 5, 2015*

**Chemistry Help**

How many moles of H2 and N2 can be formed by the decomposition of 0.250 mol of ammonia, NH3? Is it 0.250*3mol H2=0.75 0.25*1mol N2=0.25 Am I correct?
*February 28, 2015*

**Chemistry Help**

oh i got it... thank you so much
*February 27, 2015*

**Chemistry Help**

so i have to do 1/2*0.00759=0.003795 = 3.795 mL is the answer?
*February 27, 2015*

**Chemistry Help**

Ba(OH)2 is 1/2 How can you get 1/2 from.
*February 27, 2015*

**Chemistry Help**

I still have problem on how can you get mols Ba(OH)2 from. Can you explain please
*February 27, 2015*

**Chemistry Help**

How many milliliters of 0.534 M Ba(OH)2 solution are needed to completely neutralize 34.5 mL of 0.220 M HBr solution? The reaction is Ba(OH)2(aq) + 2HBr(aq) → BaBr2(aq) + 2H2O(l) I did 0.0345 * 0.220 = 0.00759 Moles of HCl =2*0.00759= 0.01518 0.01518*1000= 15.18 mL ...
*February 27, 2015*

**Chemistry Need Help**

Thanks both of your replied. I got it now :)
*February 27, 2015*

**Chemistry Need Help**

Sorry but I still don't understand your explaining. Can you explain more briefly please. Thanks.
*February 27, 2015*

**Chemistry Need Help**

Cl2 + F2 -> 2ClF
*February 27, 2015*

**Chemistry Need Help**

Given the chemical equation, Cl2 + F2 2ClF, how many moles of ClF are produced in the reaction, if 1.50 moles Cl2 are made to react with 1.75 moles F2 ? I got the answer 3.50 moles but it was wrong. Can anyone help me please.
*February 27, 2015*

**Math**

1 inch = 15 miles: Franklin to Washington is 45 Miles (3 inches) Franklin to Lincoln is 30 miles (2 inches) How much farther from Franklin is Washington than is Lincoln? I worked it out to be 7 1/2 miles but my teacher says I am wrong? She says the answer is either 11 - 17 - ...
*February 25, 2015*

**science**

two small spheres lie 1.5 meters apart and carry identical charges. How large is the charge on each if a sphere experiences a force of 2.0 N.
*February 24, 2015*

**Math**

47. For science class, Kyle needs to make a dilute solution of 12 ounces that is 30% vinegar. But he only has 20% vinegar 60^ vinegar. How many ounces of 20% vinegar should he use? A. 3 ounces B. 6 ounces C. 9 ounces D. 10 ounces
*February 18, 2015*

**Math**

In triangle ABC, the degree measure of angle A is 20 degree greater than the degree measure of angle B. Angle C is a right angle. What is the measure of angle B? Is it 70 degrees. 90-20=70
*January 28, 2015*

**Calculus**

Ohhhhhhhhh THANKS
*January 12, 2015*

**Calculus **

F(x) = 3/4x^4 –x^3 -3x^2 + 6x Determine the interval(s) where f(x) is increasing (if any) and the interval(s) where f(x) is decreasing (if any). How do I know where f(x) is increasing or decreasing?
*January 12, 2015*

**sociology**

What does "Social Space" mean when we talk about location
*January 3, 2015*

**Sociology101**

thx
*January 2, 2015*

**Sociology101**

I found out. She said APA
*January 2, 2015*

**Sociology101**

She did not tell us which writing style to use. I think MLA is the standard.
*January 2, 2015*

**Sociology101**

I have to write an essay for my Intro to Sociology class. Do I write it in MLA or APA style?
*January 2, 2015*

**Simple math**

oh, I feel you
*December 4, 2014*

**Simple math**

If Kristin buys gas at $2.69 per gallon, which includes all taxes, what percentage of the price is the state tax? What percentage is the federal tax The state tax is .8 and federal tax is .18. So would I multiply each by the total amount the gas cost?
*December 4, 2014*

**math **

Darion needs 20 pieces of string 3/8 inch in length .He cut a 4 7/8 inch piece of string into pieces that are 3/8 of a inch long each. How many more pieces of string does he need?
*November 16, 2014*

**Operations with Fractions**

Darion needs 20 pieces of string 3/8 inch in length. He cut a 4 7/8 inch piece of string into pieces that are 3/8 of an inch long each. How many more pieces of string of string does he need?
*November 15, 2014*

**Is this correct**

Anyone??
*November 11, 2014*

**Is this correct**

f(x)= 1/3x^5 + x^-2 + 3, then f'''(x) is.. I got f'''(x)= 20x^2-24x^-5
*November 11, 2014*

**math**

A florist had an equal number of red and yellow tulips. She sold 624 red tulips. Then she had 4 times as many yellow tulips as red tulips. How many tulips did she have at first. 624 X 5 ----- 3120
*October 27, 2014*

**Physics**

A 15 kg sled experiences an applied force of 5.5 N [north] and an opposing frictional force of 2.5 N [south]. If the sled starts from rest, what will be the velocity of the sled after 4.0 s?
*October 26, 2014*

**Chemistry**

What is the difference between Citric Acid C6H8O7 and H3C6H5O7? I am seeing both and don't know which is the right one. Is one a solution of citric acid? Thanks
*September 29, 2014*

**algebra**

18x+4y=-10 9x-7y=-23
*September 4, 2014*

**math**

Area of a rectangle = 221 m2; width = length = ? Should the answer be 13 or or 26
*September 2, 2014*

**Physics**

Two boys are pulling a box across a horizontal floor as shown in the figure below. vector F 1 = 50.0 N and vector F 2 = 100 N. (a) Find the resultant (or sum) force by the graphical method. (b) Find the resultant (or sum) force by the component method.
*August 25, 2014*

**Trig**

Use the given information to evaluate sin (a-b). Exact answers. No decimals. Sin a = -7/25, cot b = 8/15; neither a nor b are in quadrant III.
*May 7, 2014*

**Math**

How many roots does x to the 3rd power -2x to the 2nd power-13x-10=0 have
*April 21, 2014*

**Chemistry**

Doing some homework, are my answers right? HCN= Polar HCOOH= Polar H2CCCH2= Nonpolar Out of the following elements: Na, H, and Au order them least to greatest in the following: Eletronegativity= Na is smallest, H is second, Au is largest Ionization Energy= Na is smallest, Au ...
*April 3, 2014*

**Science**

Right Answers: True A B C C B C D
*February 3, 2014*

**chemistry**

A chemist needs a HCl solution with a molarity of less than 0.400 M for an experiment. To find out if a sample of HCl solution can be used in the lab, the chemist performs a titration to neutralize 59.2 mL of the HCl with 45 mL of 0.400 M NaOH. Based on the results, will the ...
*January 31, 2014*

**Stats**

A random sample of size 100 is drawn from a population with a standard deviation of 10. If only 5% of the time a sample mean greater than 20 is obtained, the mean of the population is ______.
*December 13, 2013*

**Math**

Thank you for the answer now I understand. For the next question I made a mistake this is the question elli has two 8 and 1/2 pound bags of mints. She plans to put 1/12 pound at each place setting. Will she have enough mints? She has 256 guests I think that means 256 place ...
*December 11, 2013*

**math**

Ellis plans to hand out door prizes as the guest arrive she has 256 guests every 6th guest will receive a mug and for every 14 guests will receive a t shirt. Which guest will be the first to receive both mug and at shirt? Next question is elli has 8 and 1/2 pound bags of mints...
*December 11, 2013*

**Math**

Explain how to use a protractor to measure an angle.
*December 3, 2013*

**Maths**

A flat circular disc, of radius R, can be modelled as a thin disc of negligible thickness. It has a surface mass density function given by f(r,φ) = k(1 - r2/R2), where k is the surface density at the centre and r is the distance from the centre of the disc.Using area ...
*October 28, 2013*

**Computer Programming using python**

DO IT BY YOURSELF OR YOU WILL NOT LEARN! GOOD LUCK!
*October 24, 2013*

**Algebra**

What is the mean of all even integers from 123 to 987?
*October 18, 2013*

**Physics **

An unmarked police car traveling a constant 80km/h is passed by a speeder traveling 135km/h. Precisely 3.00s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 1.50m/s^2 , how much time passes before the police car ...
*October 6, 2013*

**math**

sorry not 12 mths. 3200/600 = 5.3mths
*September 29, 2013*

**math**

x - 3y = 3200 y = 600 x - 3(600) = 3200 x = 5000 x/y = 12mths
*September 29, 2013*

**maths**

An initial-value problem is given by the differential equation, f(x,y) = x + y, y(0) = 1.64 The Euler-midpoint method is used to find an approximate value to y(0.1) with a step size of h = 0.1. Then use the integrating factor method, to find the exact value of y(0.1). Hence, ...
*September 29, 2013*

**Equation **

Four times a number, increased by 25 is 13 less than 6 times the number. What is the number? 4n+25=-13-6n. ???
*September 11, 2013*

**math**

I think
*September 3, 2013*

**math**

57.5 hr
*September 3, 2013*

**English **

I need to write 2 paragraphs about my favorite movie giving 4 reasons why, but don't have one. Please Help..!!
*August 5, 2013*

**Math**

I am a two digit even number. I am less than 30. When you list out all of my factors, they add up to 60. who am I?
*July 28, 2013*

**Chemistry**

Calculate delta G of a reaction with equilibrium constant, K= 9.5 x 10^5 at 25 degrees C
*July 10, 2013*

**trig, math**

There was no diagram to show me that. It was just this question.
*July 3, 2013*

**trig, math**

Given triangle ABC with a = 16, b = 14, and β = 54°, find the value of c.
*July 3, 2013*

**Python Help **

# Cis108 07/03/2014 # The PCCC Palace Hotel - Final Bill # To write a bill per party regarding there stay at the Palace Hotel including there billing invoice # Ask the user there name and number of days they will be staying in the Palace customer = input ("Enter customers...
*July 3, 2013*

**Math**

You are paneling an office that has 2 walls measuring 18' x 8' and 2 walls measuring 9' x 8'. How many sheets of paneling will you need, assuming each panel sheet measures 4' x 8'?
*June 25, 2013*

**Math**

Compute the square footage of carpet needed to cover a room 10' 6" x 12' 3". Area (to the nearest tenth) = square feet. Can you explain the steps on how to solve this problem.
*June 25, 2013*

**Math**

Tim wants to model a doll house from a real house that measures 60 feet in length by 28 feet in width. He decides to use a scale in which ¼ inch equals 1 foot. Based on this scale, What will be the length of the longer side of Tim's model? inches What will be the ...
*June 25, 2013*

**Math**

Tim wants to model a doll house from a real house that measures 60 feet in length by 28 feet in width. He decides to use a scale in which ¼ inch equals 1 foot. Based on this scale, What will be the length of the longer side of Tim's model? inches What will be the ...
*June 25, 2013*

**Math**

A vehicle covers 2,160 miles in 5.5 hours. What is the average speed of the vehicle to the nearest tenth. I got 55.5, but I don't think it is correct.
*June 25, 2013*

**Math**

Chris Shopper received a $800 discount loan to purchase a washer and dryer. The loan was offered at 10% for 120 days. What are the proceeds? I tried this problem and the answer is not 26.40
*June 24, 2013*

**Math**

hey
*May 23, 2013*

**Math**

prove identity Sin2x - sinx/cosx + cos2x= sinx/cosx + 1
*May 19, 2013*

**Language**

Read the poem and answer the questions that follow 1.There once was a cowboy named Ray 2. Who never had that much to say, 3. Except for the times 4. Stampedes stopped on a dime 5. When that cowboy named Ray hollered Hey 1.in which lines do you see repetition? 2. What is the ...
*May 10, 2013*

**Math**

Yes, I copied it correctly. I was wondering too. Thank you for your help
*May 5, 2013*

**Math**

How do you find the price of each share if 700 shares of stock are sold for $55.00 ?
*May 5, 2013*

**Math ASAP please**

#1 is p = 0.20k + 100. #4 is correct.
*April 19, 2013*

**Math**

crap, i screwed up writing my answers. Ignore them please.
*April 7, 2013*

**Math**

So I have a question regarding advanced functions, logarithm stuff. here is the question: Beginning with the function f(x) = log[base(a)]x ,state what transformations were used on this to obtain the functions given below: a) p(x) = -(5/8) log [base(a)]x b) r(x) = log[base(a)](...
*April 7, 2013*

**Calculus-Inverse Functions**

is the inverse function of x+ floor(x) equal to x - floor (x/2) i got this after plotting points but i'm not sure. thank you
*March 31, 2013*

**Calculus**

The continuity of floor functions the function: x - floor(x) it is continuous on what interval? i got all real numbers except for integers. is this right. thank you.
*March 31, 2013*

**math**

but why the choice for ln?
*March 18, 2013*

**math**

nevermind on 2), i would appreciate an asnwer to 1) though
*March 18, 2013*

**math**

I asked the following the other day and received the following answer: Posted by Matthew on Sunday, March 17, 2013 at 11:03pm. A quantity of oxygen gas had 16.32 g of the radioactive isotope oxygen-19 in it. When measured exactly 10 minutes later, the amount of oxygen-19 was 0...
*March 18, 2013*

**math**

The value, V, of a $25000 vehicle after y years is given by V = 25000 (0.85)y What is the rate of depreciation? (1 mark) What will the car be worth after 5 years? (1 mark) To the nearest month, how long would it take to reduce the vehicle’s value to 10% of its original ...
*March 17, 2013*

**math**

A quantity of oxygen gas had 16.32 g of the radioactive isotope oxygen-19 in it. When measured exactly 10 minutes later, the amount of oxygen-19 was 0.964 g. What is the half-life, in seconds, of oxygen-19?
*March 17, 2013*

**Chemistry**

An experiment requires 0.7 M NH3(aq). The stockroom manager estimates that 15 L of the base is needed. What volume of 15 M NH3(aq) will be used to prepare this amount of 0.7 M base?
*March 8, 2013*

**Please help check physical science!**

Please help check my answers I really want to make a 100%! 1. A mechanical wave moves through a medium, which can be (1 point) A. a liquid. B. a solid. C. a gas. D. all of the above <-- This one 2. Which type of kind of wave causes the medium to vibrate only in a direction ...
*March 6, 2013*

**Theoretical&Experimental Probability please help!**

Please check my work thanks!! A number cube with the numbers 1 through 6 is rolled. Find the given probability. 1. P(number < 2) (1 point) A. 1/6 <--- i think this one B. 2/6 C. 4/6 D. 3/6 2. P(number ≥ 3) (1 point) A. 4/6 B. 1/6 C. 2/6 <-- this i think D. 5/6 ...
*March 6, 2013*

**Math**

It would be less then the World because of the international and if you add the cost of how much it is the answer shows you that it's less.
*March 2, 2013*

**algebra**

real world situation a problem describing incresing then constant and finally decreasing
*February 19, 2013*

**Science**

a 5-kilowatt source powers a motor that is lifting a 30 kg mass straight up. how far will the mass move in 6 seconds
*February 14, 2013*

**math 5th**

help
*February 12, 2013*

**Soc. Studies**

1.D 2.A 3.C 4.C
*February 11, 2013*

**math**

Burj Khalifa is the world tallest building in Dubai at 828 m tall. The CN Tower in Toronto is 553 m tall. Sam wants to compare the Burj Khalifa and the CN Tower by creating rectangular prism models on a 10 cm by 10 cm square base. She has decided to represent the Burj Khalifa ...
*January 15, 2013*

**Computer**

More than likely the computer requires more memory.
*January 10, 2013*

**Math**

Several friends are taking turns flying a kite. Each friend flies the kite for the same amount of time. They spend 6 hours flying the kite altogether. Explain what information you need to find how long each friend flew the kite for.
*January 7, 2013*

**Chemistry**

A 208 g sample of sodium-24 decays to 13.0 g of sodium-24 within 60.0 h. What is the half-life of this radioactive isotope?
*December 11, 2012*

**Chemistry**

All isotopes of technetium are radioactive, but they have widely varying half-lives. If an 800.0 g sample of technetium-99 decays to 100.0 g of technetium-99 in 639,000 y, what is its half life
*December 11, 2012*

**Chemistry**

What is the half-life of a 100.0 g sample of nitrogen-16 that decays to 12.5 g of nitrogen-16 in 21.6 s? Please help me!!
*December 11, 2012*

**TRIGONOMETRY**

Write the following trigonometric expression as an algebraic expression in x free of trigonometric or inverse trigonometric functions sin(cos^-1 x) -1≤x≤1
*December 4, 2012*

**math**

3.56kg = G
*November 27, 2012*