Monday

September 26, 2016
Total # Posts: 3,235

**Physics**

If one firework produces a sound intensity of 90 dB, what would be the intensity of a sound produced by 1000 firecrackers all going off at once?

*February 17, 2011*

**chem-repost**

How many grams of magnesium oxide are formed when 13.5 L of oxygen gas, measured at STP, completely reacts with magnesium metal according to the following reaction? i got .496 g but i know that like way off

*February 17, 2011*

**9th grade polynomials**

area= lX w so by substituting the numbers and variables for the lenght and using x for the width we get area= (2+3x) X x

*February 17, 2011*

**chem**

How many grams of magnesium oxide are formed when 13.5 L of oxygen gas, measured at STP, completely reacts with magnesium metal according to the following reaction? i got .496 g but i know that like way off

*February 17, 2011*

**Economics**

so how is that trying to reduce the poverty trap and how is not?

*February 16, 2011*

**Economics**

Ok sorry about that. So far I have that is the minimum wage is increased then those who get benefits will nnot receive them anymore as they are having higher incomes. I also said that increasing the minimum wage will reduce the poverty trap because it gives employees an ...

*February 16, 2011*

**Economics**

Discuss whether the minimum wage will reduce the poverty trap? I need 3 ways for and 3 ways against

*February 16, 2011*

**chem**

A balloon holds 29.3 kg of helium. What is the volume of the balloon if the final pressure is 1.2 atm and the temperature is 22°C? using the equation pv=nrt would i put 29.3 kg in place of n? but n has to be in moles so how do you convert that? thanks

*February 14, 2011*

**chem**

nvm i got it

*February 14, 2011*

**chem**

An experiment shows that a 114 mL gas sample has a mass of 0.167 g at a pressure of 721 mm Hg and a temperature of 32°C. What is the molar mass of the gas? so im suppose to find the molar mass but i thought that was the same as the g just converting it..? im using the ...

*February 14, 2011*

**Chemistry**

How many grams of potassium carbonate are needed to make 0.200 L of a 2.50M solution?

*February 13, 2011*

**Math**

The cost of Mrs.Taylors purchases was $45.87 She had a coupon for 20% off the total. Find, to the nearest cent, the amount of money she will save if she uses the coupon?

*February 10, 2011*

**Math**

The cost of Mrs.Taylors purchases was $45.87 She had a coupon for 20% off the total. Find, to the nearest cent, the amount of money she will save if she uses the coupon?

*February 10, 2011*

**physics for dummies! **

The man hanging upside down is holding a partner who weighs 699 N. Assume that the partner moves on a circle that has a radius of 3.37 m. At a swinging speed of 3.49 m/s, what force must the man apply to his partner in the straight-down position?

*February 10, 2011*

**physics cars! **

Car A uses tires for which the coefficient of static friction is 0.175 on a particular unbanked curve. The maximum speed at which the car can negotiate this curve is 28.3 m/s. Car B uses tires for which the coefficient of static friction is 0.740 on the same curve. The cars of...

*February 10, 2011*

**physics help go!**

Two cars are traveling at the same speed of 27 m/s on a curve that has a radius of 126 m. Car A has a mass of 1020 kg, and car B has a mass of 1670 kg. Find (a) the magnitude of the centripetal acceleration and (b) the magnitude of the centripetal force for Car A, (c) the ...

*February 10, 2011*

**Ch. 5 physics help! **

There is a clever kitchen gadget for drying lettuce leaves after you wash them. It consists of a cylindrical container mounted so that it can be rotated about its axis by turning a hand crank. The outer wall of the cylinder is perforated with small holes. You put the wet ...

*February 10, 2011*

**physics please help! 116**

Two blocks are connected by a rope that passes over a set of pulleys. One block has a weight of 412 N, and the other has a weight of 908 N. The rope and the pulleys are massless and there is no friction. (a) What is the acceleration of the lighter block? (b) Suppose that the ...

*February 10, 2011*

**physics help please! **

A spacecraft is on a journey to the moon. At what point, as measured from the center of the earth, does the gravitational force exerted on the spacecraft by the earth balance that exerted by the moon? This point lies on a line between the centers of the earth and the moon. The...

*February 10, 2011*

**physics 2 help please! **

The space probe Deep Space 1 was launched on October 24, 1998. Its mass was 474 kg. The goal of the mission was to test a new kind of engine called an ion propulsion drive. This engine generates only a weak thrust, but it can do so over long periods of time with the ...

*February 10, 2011*

**physics 1 please help!**

A man seeking to set a world record wants to tow a 106000-kg airplane along a runway by pulling horizontally on a cable attached to the airplane. The mass of the man is 77 kg, and the coefficient of static friction between his shoes and the runway is 0.99. What is the greatest...

*February 10, 2011*

**physics 1 please help!**

A man seeking to set a world record wants to tow a 106000-kg airplane along a runway by pulling horizontally on a cable attached to the airplane. The mass of the man is 77 kg, and the coefficient of static friction between his shoes and the runway is 0.99. What is the greatest...

*February 10, 2011*

**Algebra**

A roadside vegetable stand sells pumpkins for $5 each and squash for $3 each. One day they sold six more squash then pumpkins and their sales totaled $98.00. Write a system of equations to find the number of pumpkins and squash they sold.

*February 10, 2011*

**chem**

i need help on this question: Equal masses of gaseous N2 and Ar are placed in separate flasks of equal volume at the same temperature. Tell whether each of the following statements is true or false. a) There are more molecules of N2 are present than atoms of Ar. true or false...

*February 10, 2011*

**World Geography**

What are three ways geography influenced Roman History?

*February 9, 2011*

**math**

if csc theta= -5/3 and theta has its terminal side in quadrant III, find the exact value of tan 2 theta.

*February 8, 2011*

**English**

for "Children of the River" I have to come up with a thesis statement for chapter 1 I dont know what it is.....please help

*February 7, 2011*

**Algebra 1**

What property justifies that 3y+9 = 9+3y

*February 7, 2011*

**Math(Please check)**

What is the difference between the actual increase in profit as production increases from 5 to 6 units, and the marginal profit at a production level of 5 units where the profit function is given by p(x)= 3x^2 - 5x + 2 First I plugged 5 into the equation and got 52. Then I ...

*February 5, 2011*

**Math(Please check)**

Find the slope of the graph at y=sqrt 2x^2 +1 at the point (2,3). First I plugged 2 into the equation and got 3. Then the derivative of the equation is 4x and then I multiplied that by 3 and got 12. Is this correct?

*February 5, 2011*

**Math**

Find the derivative of f(x)= 2 sqrt x at x=4. i thought that the derivative would be 2 x^1/2 but I guess this is wrong.

*February 5, 2011*

**Math**

Calculate the limit limit x->infinity 2x^2 + 100 / x^2 +1 I am not sure how to do this.

*February 1, 2011*

**Math**

Find the slope of the curve at y=x^6 at x=-3. I know that to find the slope you do y2 - y1 / x2 - x1 but I do not know what to do here.

*January 30, 2011*

**Math(Please check)**

So if though it says that the rate at which the epidemic is spreading is 110 per day that is not rate of change correct?

*January 30, 2011*

**Math(Please check)**

During the month of February, a flu epidemic hit the University. The number of people sick at time t (measured in days) is given by the function P(t). The rate at which the epidemic is spreading on February 3 is 110 people per day. How is the information best represented ...

*January 30, 2011*

**Math(Please check)**

I had the negative sign there because thatg was one of the answer choices that best fit what I had but there is no negative correct? Its positive?

*January 30, 2011*

**Math(Please check)**

Find the derivative of f(x)=1/3 sqrt x. The 3 is little above the square root. I know that it is -1/3x^-4/3. Can this be written as -1/3x^4/3 ?

*January 30, 2011*

**Math(Please check)**

Another answer choice was y=-2076x + 15,780. Is this correct? If it is I do not understand how they go -2076. Thank you for your help!

*January 30, 2011*

**Math(Please check)**

The value of an automobile was $15,780 in 1994 and depreciated to $5400 in 1999. Let y be the value of the automobile in the year x, where x = 0 represents 1994. Write a linear equation in slope-intercept form that models the value y of the automobile, x years after 1994. ...

*January 30, 2011*

**Math(Please check)**

Thank You

*January 30, 2011*

**Math(Please check)**

Find the derivative of f(x)=7x-19 at x=2. I think that the derivative would be 7 and theb times 2 so 14. Is this correct or would it just be 7.

*January 30, 2011*

**chem**

I know carbon is tetrahedral but i dont know oxygen

*January 29, 2011*

**chem**

I dont get how to the structure and how to find oxygen separetley

*January 29, 2011*

**chem**

Determine the electron and molecular geometries of each of the following molecules. For those with more than one central atom, indicate the geometry about each central atom. (Enter your answers in the order given in the skeletal structure from left to right.) CH3OH (skeletal ...

*January 29, 2011*

**What do taxes pay for**

RACEMIDE

*January 28, 2011*

**Help**

Thanks, it didn't look right thats why I reposted

*January 27, 2011*

**Help**

I get x=3 can you let me know if I have it right

*January 27, 2011*

**Help**

Is there a website that will help me solve this? I can't find anything. I'm coming up with x=1/3 but I feel I'm doing it wrong. Find all real number solutions to (cubed root 3x-8)-1=0 If there is more than one solution, separate them with commas. If there is no ...

*January 27, 2011*

**Math**

Is is x=1/3

*January 27, 2011*

**Math**

Find all real number solutions to (cubed root 3x-8)-1=0 If there is more than one solution, separate them with commas. If there is no solution, answer as "No solution."

*January 27, 2011*

**Health**

thanks, do you have any other suggestions?

*January 27, 2011*

**Health**

I need an example of a health fraud item/ product. I need to find one product that has health fraud and that I can write 150 words about. I tried searching on google but cant find anything/ dont know what to search. do you know of any products? thanks

*January 27, 2011*

**History**

Describe an advantage of havinf federal judges appointed rather then elected

*January 26, 2011*

**History**

Why is it important to learn about the government?

*January 26, 2011*

**History**

What problems might arise from making the runner-up in the presidential election the vice president?

*January 25, 2011*

**math**

I have no idea... :)

*January 24, 2011*

**chem**

thanks:)

*January 20, 2011*

**chem**

For each of the following sets of atoms and ions, arrange the members in order of increasing size. Mg2+ F- and Na+

*January 20, 2011*

**algebra**

whats the lcd of 8/9x+2/3x=1/9x+45

*January 20, 2011*

**science**

can you unscrample this word? its in french. "ratuere"

*January 20, 2011*

**5th grade algebra **

Omg thanks so much!!!

*January 19, 2011*

**5th grade algebra **

I need help with input out put table. The top row is: 1, 4, 3 5 8 9 6 The bot row is: 1, 10,7,13 ? ? ? The question marks are blanks in the table. Hellllllp please

*January 19, 2011*

**Math**

I am looking for help integrating using u substitution over the interval of 0 to pi/2 the function cos(2x/3)

*January 17, 2011*

**Math**

Solve integration using u substitution of (x+1)sqrt(2-x)dx

*January 17, 2011*

**Math**

Solve integration using u substitution of (x+1)sqrt(2-x)dx

*January 17, 2011*

**Physics**

d^2=(k*Q1*Q2)/F d^2=(8.99*10^9)(60*10^-6uC)(50*10^-6uC)/175 d^2=0.154 square root of d^2= square root of 0.154 d=0.392m or 3.92cm

*January 16, 2011*

**chem**

oh i got it:) thanks:):)

*January 13, 2011*

**chem**

i tried [Kr]5s24d8 but it didnt work

*January 13, 2011*

**chem**

Use the periodic table to write electron configurations for each of the following elements. (Type your answer using the format [Ar] 4s2 3d10 4p2 for [Ar]4s23d104p2.) 1. Pd thanks

*January 13, 2011*

**chemistry**

How many grams of oxygen gas are reacted if 75 g of hydrogen gas is consumed?

*January 13, 2011*

**science**

How does a tennis ball change shape when you hit it?

*January 10, 2011*

**Physics**

Consider the 676 N weight held by two cables shown below. The left-hand cable had tension 740 N and makes an angle of θ with the wall. The right-hand cable had tension 730 N and makes an angle of θ1 with the ceiling. a) What is the angle θ1 which the righthand ...

*January 8, 2011*

**chem**

What is the frequency of radiation whose wavelength is 26.80 Angstrum ? at first i got 1.000e17 and it was wrong. now i only have 1 more try. i tried it again and got 9.993e16 but i dont want to put it in unless its correct. can you guys check my work?

*January 8, 2011*

**Calculus**

Find dy/dx, y= -7e^6x+11 + xe^x

*December 16, 2010*

**science**

what properties of carbon explain its ability to form many macromolecules?

*December 15, 2010*

** physics**

A car moving at 20m/s is sounding its horn as it approaches you. If the actual frequency of the horn is 283 Hz, what frequency will you hear at 25.0 degrees C?

*December 15, 2010*

**Thermochemistry**

How many grams of water at 0 degrees C can be frozen into ice at 0 degrees C if 55.0 kJ of heat is removed? delta Hsolid= -6.01 kJ/mol

*December 14, 2010*

**Thermochemistry**

3CO(g)+ Fe2O3(s) --> 2Fe(s) + 3CO2(g) + 24.7 kJ. How much heat is released when 56 grams of CO react?

*December 14, 2010*

**Chemistry**

The molar heat of solution of NH4NO3 is 25.7 kJ/mol. How much heat (in kJ) would be required to dissolve 20 grams of NH4NO3 in water?

*December 14, 2010*

**Chemistry**

How much heat is required to convert 9 grams of water at 100 degrees C into steam at 100 degrees C. Hvap for water = 40.7 kJ/mol

*December 14, 2010*

**Chemistry**

Si(s)+ 2Cl2(g) --> SiCl2(g) --> SiCl2(l) + 687 kJ. How much heat is produced when 106 grams of Cl2 react?

*December 14, 2010*

**Chemistry**

A student mixes two water solutions with an initial temperature of 25 degrees C to form a final substance with a mass of 65 grams at 30 degrees C. What is the heat change in kJ?

*December 14, 2010*

**Chemistry**

How much heat in kJ is required to melt 54 grams of ice at 0 degrees C into water at 0 degrees C if delta Hvap for water = 6.01 kJ/mol?

*December 14, 2010*

**Chemistry**

How many calories are required to raise the temperature of 75 grams of water from 20 degrees C to 50 degrees C?

*December 14, 2010*

**question about corrections(what they mean)**

ok thanks:)

*December 13, 2010*

**question about corrections(what they mean)**

ok. so this may be hard to explain and may not be enough info that you understand but ill try. I did a paper and my teacher corrected it and said changes i need to make. here is a clip from the paper of something that she commented on: " Here are some examples. Hard Tack ...

*December 13, 2010*

**english- need a creative title!**

thanks for the idea. That would probably work but I don't know if my teacher would understand it because that is not one of the slang words i described in my paper. do you have any other ideas?

*December 13, 2010*

**english- need a creative title!**

For my english class i had to right a paper on civil war slang and how this topic releated to the book The Red Badge of Courage. I finished my paper but have no idea of a creative title. Im not good at thinking up good titles :/ have any ideas?

*December 13, 2010*

**Algebra**

why is any real number a solution for the equation 8y - 30 = 4(2y - 7.5)

*December 12, 2010*

**chem**

i dont think 34 is correct because that is way more than 10% of my first answer of 5.7

*December 11, 2010*

**chem**

Some sulfuric acid is spilled on a lab bench. It can be neutralized by sprinkling sodium bicarbonate on it and then mopping up the resultant solution. The sodium bicarbonate reacts with sulfuric acid as follows. 2 NaHCO3(s) + H2SO4(aq) --> Na2SO4(aq) + 2 H2O(l) + 2 CO2(g) ...

*December 11, 2010*

**Math**

A population is 200 in the year 1825, 252 in 1850, and 318 in 1875. What is the p(t) equation? I see that the population increases 26% over each 25-year period but I can't figure out the equation.

*December 9, 2010*

**Math**

Dina earned 1/4 for baby sitting and 1/2 for washing the dishes. How much money did she NOT earn from $25.00?

*December 9, 2010*

**Geometry **

sam..? im assuming just like the others we cannot see your documents so we don't know what the picture looks like. sorry

*December 9, 2010*

**chem**

thanks for the help: can you help me with another one? Some sulfuric acid is spilled on a lab bench. It can be neutralized by sprinkling sodium bicarbonate on it and then mopping up the resultant solution. The sodium bicarbonate reacts with sulfuric acid as follows. 2 NaHCO3(s...

*December 9, 2010*

**chem**

thanks so its 5.21 L h2?

*December 9, 2010*

**chem**

2Al(s) + 2NaOH(aq) + 2H2O(l) 2NaAlO2(aq) + 3H2(g) (unbalanced) sorry i forgot. it was unbalanced but then i balance it

*December 9, 2010*

**chem**

Calculate the number of liters of hydrogen, measured at STP, that can be produced from the reaction of 0.155 mol of aluminum according to the following unbalanced chemical reaction equation. i got .193 L of H2 but it was wrong. i only have one submition left!

*December 9, 2010*

**Geometry Please Help**

im sorry your link/document doesnt work

*December 9, 2010*

**chem- plz check my work**

2. Given the following equation, C2H5OH(l) + 3 O2(g)---> 2 CO2(g) + 3 H2O(l) How many liter of CO2 are expected in the combustion of 12.0 grams of ethanol? My work: 12.0g C2H5OH X 1 mol C2H5OH/46.08g C2H5OH X 2 mol CO2/1 molC2H5OH X 22.4L CO2/1 mol CO2 = 11.7 L CO2 all i ...

*December 8, 2010*