# Posts by David

Total # Posts: 2,249

**chemistry**

how many grams of ethenol do i need to burn in excess oxygen in order to recover 5.0 g of h2o in a 75% yield

*January 27, 2011*

**geometry**

francisco designed a triangular garden surrounded by three square gardens. the area of garden c (the largest garden) is 400 sq. ft. and the length of a side of garden b is 12 ft. find the lengths of all sides of the triangular gardens and find the areas of the gardens. draw a ...

*January 27, 2011*

**Com 220**

How does the author of “A Nation Apart” organize information to build his argument? He organizes the information by first presenting problems of China's economic issues. He then goes on to show you some statistics from his sources and quotes the leaders that play...

*January 27, 2011*

**joe has a mass of 50 kg and sally has a madphysics**

joe has a mass of 50 kg and sally has a mads of 30 kg. they sit in class with a separation of 0.5 meters. Find hhe gravitational attraction between joe and sally

*January 27, 2011*

**Precalc**

First divide 500 from both sides Leaving e^.3x=1.2 Take ln e^.3x=Ln1.2 .3x ln e^.3x=ln1.2 (note:ln e=1 .3x=ln 1.2 x=(ln 1.2/.3) x=.60774

*January 26, 2011*

**algebra**

8.775 x 10^-1

*January 26, 2011*

**Algebra**

c^4/a^4 I believe is the answer

*January 26, 2011*

**Algebra**

I am trying to solve (2*(c^4)*2*(a^6))/(2*(a^10)) but the answer I am getting is 2c^4a^4. Do you know if this is correct?

*January 26, 2011*

**ChemistryDrBob222**

Arrows disappeared from below added them back to the equations. ??(a) I don't understand ln(No/N)=akt The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (...

*January 26, 2011*

**ChemistryDrBob222**

Arrows disappeared from below added them back to the equations. The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in minutes, will it take for [...

*January 26, 2011*

**Algebra**

Distance formula 1=((x-0)^2 +(x^3-0)^2)^1/2 1=(x^2+x^6) 0=x^6+x^2-0 Use x=1 and x=.5 Use bisection method to continue to the nearest tenth x=.83 and y=.83^3=y=.56 The points are -.83,-.56,.56,and .83

*January 26, 2011*

**Algebra**

Use the bisection method or a graphing calculator to find the coordinates of the two points on the graph of that lie r = 1 unit from the origin. Give the result to the nearest hundredth, I just need a direction to go on this problem

*January 26, 2011*

**calculus**

Use the bisection method or a graphing calculator to find the coordinates of the two points on the graph of that lie r = 1 unit from the origin. Give the result to the nearest hundredth, I just need a direction to go on this problem

*January 26, 2011*

**Algebra**

y=-1/3 x+8 y-7=-1/3(x-4) y=-1/3 x +25/3

*January 26, 2011*

**physics**

Suppose 3 mols of neon (an ideal monatomic gas) at STP are compressed slowly and isothermally to 0.19 the original volume. The gas is then allowed to expand quickly and adiabatically back to its original volume. Find the highest temperature attained by the gas. Find the lowest...

*January 26, 2011*

**Algebra 1**

Answer The two even sides are 135 And the shorter side is 45

*January 26, 2011*

**algebra**

Distance=Rate/time 50(Time)=32(Time + 2 hours)+17 50 x t = 32t + 64 +17 50t = 32t +81 50t-32t=81 18t=81 t=4.5 Plug this in to the origional equation 50(4.5)= 225 miles to New York Check answer 32(4.5 +2)+17=225 I hope this clears up this problem for you

*January 26, 2011*

**Algebra**

First to find slope -8--6/(-4)-(-1) = slope 2/3 Substituting y-(-8)=2/3 (x-(-4) y=2/3x-16/3

*January 25, 2011*

**Pre-Algebra**

On a trip from Lousiana to Flordia, your family wants to travel at least 420 miles in 8 hours of driving. Write and solve an inequality to find what your average speed must be.

*January 25, 2011*

**Math Geometry**

The angle bisector of one angle of a triangle forms two angles that measure 27 degrees. The angle bisector of another angle forms two angles that measure 34 degree. What is the measure of the third angle of the triangle?

*January 25, 2011*

**Math Geometry**

A right triangle has one angle that measures 16 degrees. What are the measures of the other two angles?

*January 25, 2011*

**phoenix**

o Find a movie review in an online publication for a movie currently playing in theaters. Post the link to the review for the class and provide five examples of how the reviewer used adverbs and five examples of the use of adjectives. Has the reviewer used them effectively? ...

*January 25, 2011*

**Chemistry**

The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in minutes, will it take for [IBr] to go from 0.500M to 0.100M? (c)What is the half-life for ...

*January 24, 2011*

**Chemistry**

The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in minutes, will it take for [IBr] to go from 0.500M to 0.100M? (c)What is the half-life for ...

*January 24, 2011*

**Physics**

An airplane must reach a speed of 185 mi/h to take off. If the runway is 467 m long, what is the minimum value of the acceleration that will allow the airplane to take off successfully? m/s2 I have been trying the formula vf^2=Vi^2+2AD and solving for A SO my work has been 185...

*January 23, 2011*

**physics**

E= 2.5 X 10^5 N/C

*January 23, 2011*

**Chemistry**

The decomposition of IBr(g)into I2 (g) and Br2 (g) is first order in IBr with k = 0.00255/sec. (a)Starting with [IBr] = 1.50M, what will [IBr] become after 2.50 minutes? (b)How long, in minutes, will it take for [IBr] to go from 0.500M to 0.100M? (c)What is the half-life for ...

*January 23, 2011*

**physics**

Two cars start from rest at the same location and at the same instant and race along a straight track. Car A accelerates at 6.6 fps2 to a speed of 90 mph and then runs at this constant speed. Car B accelerates at 4.4 fps2 to a speed of 96 mph and then runs a a constant speed...

*January 22, 2011*

**College Accounting**

Apr. 1 Cash $40,000.00 Capital $40,000.00 Apr. 4 Land $30,000.00 Cash $30,000.00 Apr. 8 Advertising $1,800.00 Accounts Payable $1,800.00 Apr. 11 Salaries $1,800.00 Cash $1,800.00 Apr. 13 Prepaid Insurance $1,500.00 Cash $1,500.00 Apr. 17 Drawing $1,000.00 Cash $1,000.00 Apr. ...

*January 15, 2011*

**physics**

A certain spring stretches 5.3 cm when it supports a mass of 0.65 kg . If the elastic limit is not reached, how far will it stretch when it supports a mass of 10 kg ? Answer in cm

*January 12, 2011*

**Physics**

Some enterprising physics students working on a catapult decide to have a water balloon fight in the school hallway. The ceiling is of height 3.2 m, and the balloons are launched at a velocity of 12 m/s. The acceleration of gravity is 9.8 m/s2 . At what angle must they be ...

*January 12, 2011*

**physics**

Some enterprising physics students working on a catapult decide to have a water balloon fight in the school hallway. The ceiling is of height 3.2 m, and the balloons are launched at a velocity of 12 m/s. The acceleration of gravity is 9.8 m/s2 . At what angle must they be ...

*January 11, 2011*

**Physics**

A certain spring stretches 5.3 cm when it supports a mass of 0.65 kg . If the elastic limit is not reached, how far will it stretch when it supports a mass of 10 kg ?Answer in units of cm

*January 11, 2011*

**physics**

You place a box weighing 302.1 N on an in- clined plane that makes a 35.6 angle with the horizontal. Compute the component of the gravita- tional force acting down the inclined plane. Answer in units of N.

*January 11, 2011*

**Algebra**

Hi. I am having some problems with substitution method and i just can't seem to get these right. I have 1. 2x - 3y = -1 with y = x-1 2. -4x + y = 6 with -5x- y = 21 and finally, 3. -5x + y =-3 with 3x -8y = 24

*January 8, 2011*

**Algebra**

Hi. I am having some problems with substitution method and i just can't seem to get these right. I have 1. 2x - 3y = -1 with y = x-1 2. -4x + y = 6 with -5x- y = 21 and finally, 3. -5x + y =-3 with 3x -8y = 24

*January 8, 2011*

**math**

a christmas tree is 34 feet tall. it casts a shadow 24 feet long. toms christmas tree is standing beside the tree at rockefeller center and is 5 feet 8 inches tall. how long of a shadow would toms tree cast?

*January 2, 2011*

**psychology**

the paralysis was the unconscious way of dealing with his impulse (id) to hit his father?

*December 17, 2010*

**4th grade**

Nick had 1 3/4 gallon of milk. How many pints of milk does Nick have.

*December 15, 2010*

**algebra**

the solution to the system of equations y= 2x and y = -x + 3 is a)2,1 b)(-1,2) c)2,-1) d)(1,2)

*December 15, 2010*

**algebra**

thank you gabby!!!!!!!!!!!!

*December 15, 2010*

**algebra**

the solutions to the system of equations y= 2x and y =-x + 3 is a)2,1 b)(-1,2) c)2,-1) d)(1,2)

*December 15, 2010*

**12th grade**

one type of probability used everyday is: a)experienced probability b)scientific probability c)frequency of occurence d)none of the above

*December 15, 2010*

**math**

when you put something in parenthesis like C(25,8) what does that mean or how do you solve it?

*December 15, 2010*

**Math**

Suppose you are managing 25 employees, and you need to form three teams to work on three different projects. Assume that all employees will work on exactly one team. Also, each employee has the same qualifications/skills, so any employee can serve on any team. The number of ...

*December 15, 2010*

**Algebra**

x = 0.5 4x = 2 4(0.5) = y - 1 +1 on both sides... y = 3! Thanks!

*December 14, 2010*

**Algebra**

I know but wouldn't you have to go through confusing fractions and multiply by fractions to get a whole number of x? I am trying to follow the teachers directions which do not include fractions.......

*December 14, 2010*

**Algebra**

Slove each system by substitution. 4x = y - 1 6x - 2y = -3 I have already attempted this problem and couldn't figure out what I should do. I came out with 4x + 1 = 3x + 1.5 I think this looks right because our teacher told us that for this specific problem that we should ...

*December 14, 2010*

**physics**

1.) A vertical spring with a spring constant of 450 N/m is mounted on the floor. From directly above the spring, which is unstrained, a 0.30 kg block is dropped from rest. It collides with and sticks to the spring, which is compressed 2.5 cm in bringing the block to a ...

*December 13, 2010*

**physics**

A string has a linear density of 8.5*10^-3 kg and is under the tension of 280 N. The string is 1.8 m long, is fixed at both ends, and vibrating in the standing wave pattern. What is the speed, length, and frequency?

*December 12, 2010*

**physics**

1.) The average sound intensity inside a busy neighborhood restaurant is 3.*10^-5 W/M^2. How much energy goes into each ear (area = 2.1 * 10^-2 m^2) during a one hour meal? 2.) A member of an aircraft maintenance crew wears protective earplugs that reduce the sound intensity ...

*December 12, 2010*

**physics**

The length of a simple pendulum is 0.79m and the mass of the particle at the end of the cable is 0.24 kg. The pendulum is pulled away from its equilibrium position by an angle of 8.5 degrees and released from rest. Assume that friction can be neglected and that the resulting ...

*December 12, 2010*

**physics**

1.) A vertical spring with a spring constant of 450 N/m is mounted on the floor. From directly above the spring, which is unstrained, a 0.30 kg block is dropped from rest. It collides with and sticks to the spring, which is compressed 2.5 cm in bringing the block to a ...

*December 12, 2010*

**algebra**

Find the mean for each set of data. Round to the nearest tenth if necessary. 12, 20, 8, 15, 16, 14, 7, 5, 11, 8, 14 a. 11.8 b. 13.2 c. 9.9 d. 10.4 My answer a)11.8

*December 12, 2010*

**Calculus**

prove that out of the rectangles under the curve = e raised to the power of -xsquared on the x axis and upper vertices on the curve, the one has the largest area the two upper vertices of which are exactly at the points of inflection of the curve.

*December 11, 2010*

**engineering science**

The power in a resistor RLOAD of 10 Ω when connected to a 100 volt supply is measured using a voltmeter and ammeter. There are two possible ways of connecting the meters as shown in FIGURE 2. The resistances RA and RV represent the internal resistances of the ammeter and ...

*December 9, 2010*

**trigonometry**

equation of circle passing through P(10,3), Q(11,8), and R(7,14).

*December 2, 2010*

**math**

what is a slope intercept?

*December 1, 2010*

**chemistry**

in outo engine whith no pollusion controls, about 5% of the fuel(assume 100%actane c8H18)is unburned .calculate the mass and volume ratio of Co to C8H18 in exhaust gas? 2C8H18+17O2 =16CO+18H2O

*December 1, 2010*

**Chemistry**

Which of the following electron configurations is not consistent with Hund's rule? 1) 1s^2 2s^2 2p^2 3s^1 2) 1s^2 2s^2 2p^6 3s^2 3p^5 3) 1s^2 2s^2 2p^6 3s^3 3p^6 4) 1s^2 2s^2 2px^2 2py^1

*November 29, 2010*

**Chemistry**

Which of the following electron configurations is not consistent with Hund's rule? 1) 1s^2 2s^2 2p^2 3s^1 2) 1s^2 2s^2 2p^6 3s^2 3p^5 3) 1s^2 2s^2 2p^6 3s^3 3p^6 4) 1s^2 2s^2 2px^2 2py^1

*November 29, 2010*

**Physics**

An aluminum cylinder with a density of 2.70 g/cm3 has a volume of 3.8 ¡¿ 10-5 m3. If the cylinder is suspended from a scale and immersed in an unknown fluid, the scale reads 0.581 N? What is the specific gravity of the fluid?

*November 23, 2010*

**college chemistry**

Being that FeO has a metal in it and a pretty strong bonding force, I would say Iron(II)Oxide. CO2 is low, H2O is 0 degrees Celsius, and sugar is relatively low as well.

*November 18, 2010*

**geometry**

francisco designed a triangular garden surrounded by three square gardens. the area of garden c (the largest garden) is 400 sq. ft. and the length of a side of garden b is 12 ft. find the lengths of all sides of the triangular gardens and find the areas of the gardens. draw a ...

*November 18, 2010*

**physics**

wow. that was simple. thank you.. i should read the question more carefully next time :D

*November 18, 2010*

**physics**

A 52 g mountain climber, start from rest, climbs a vertical distance of 730 m. At top, she is again at rest. In the process, her body generates 4.1*10^6 J of energy via metabolic processes. Her body acts like a heat engine with efficiency ( W/Q_h.) W is the magnitude of work ...

*November 18, 2010*

**science**

. What must happen in order for a sound wave to form? A. An electric current must flow. B. A certain frequency must be reached. C. Matter must vibrate. D. Volume must be absorbed.

*November 17, 2010*

**Algebra**

This is about direct variation. The area a painter can paint varies directly with the amount of time he works. One morninig, he painted 204 ft² between 8 a.m. and 12:15 PM. Write a direct variation equation to describe the area y covered in x hours. The forumlua for ...

*November 17, 2010*

**Algebra**

This is my third question about direct variation. For this problem, tell whether each relationship is a direct variation. Explain. x | -1 | 5 | 8 | y | -1.5 | 7.5 | 12 |

*November 17, 2010*

**Algebra**

This is question 2 about direct variation For this problem, tell whether each relationship is a direct variation. Explain. x | 8 | 0 | -5 | y | 13 | 5 | 0 |

*November 17, 2010*

**Algebra**

For this problem, tell whether each relationship is a direct variation. Explain. x | -3 | -6 | -9 | y | 18 | 36 | 54 | My teacher didn't really explain direct variation very well, but i did catch that you put x over y. (Hopefully this helps)

*November 17, 2010*

**chemistry**

I worked it out to need 8458.6K would this seem like resonable value? thank you for you're help

*November 17, 2010*

**chemistry**

I think charles law is needed were pressure and mole mass is constant, temperature and volume varies. Im stuck putting it all together.

*November 17, 2010*

**chemistry**

how do I calculate what temperature is needed to heat 52 grams of ethane to occupy 1200ml?

*November 17, 2010*

**physics**

An object is solid throughout. When the object is completely submerged in ethanol alcohol., its apparent weight is 15.2 N. When completely submerged in water, its weight is 13.7 N. What is its volume? Steps please.. answer isnt really necessary

*November 17, 2010*

**Physics/Chemistry**

few other questions. 1.) Suppose you expend 430 kilocalories during a long walk, how many liters of ice water at 0 degrees do you need to consume in order to use up the 430 kilocalories of metabolic energy. Stomach can hold 1 liter. 2. A person eats a container of strawberry ...

*November 17, 2010*

**Physics**

An object is solid throughout. When the object is completely submerged in ethanol alcohol., its apparent weight is 15.2 N. When completely submerged in water, its weight is 13.7 N. What is its volume? Steps please.. answer isnt really necessary

*November 17, 2010*

**Physics/Chemistry**

few other questions. 1.) Suppose you expend 430 kilocalories during a long walk, how many liters of ice water at 0 degrees do you need to consume in order to use up the 430 kilocalories of metabolic energy. Stomach can hold 1 liter. 2. A person eats a container of strawberry ...

*November 17, 2010*

**physics**

An object is solid throughout. When the object is completely submerged in ethanol alcohol., its apparent weight is 15.2 N. When completely submerged in water, its weight is 13.7 N. What is its volume? Steps please.. answer isnt really necessary

*November 17, 2010*

**C++ Programming**

Where would I find a great video resource for learning Visual C++ for beginners? I'm a newbie and I'm looking in some code for a project on sourceforge that i'm interested in. however, I don't know C++ so i don't know how to contribute to this program. ...

*November 16, 2010*

**math**

While on his way to school, Norman saw that the cost of gasoline was $2.50 per gallon. Write a direct variation equation to describe the cost y of x gallons of gas. Then graph.

*November 16, 2010*

**Chemistry**

Hi there, I am doing some data calculations for my lab, but I'm having some trouble. Given: Mass of ferrous ammonium sulfate=4.0g Mass of K3[Fe(C204)3] 3H20 =4.53g 1. Using the above mass of ferrous ammonium sulfate, calculate the theoretical yield of the K3[Fe(C204)3] ...

*November 16, 2010*

**Quick Question**

yes.

*November 16, 2010*

**math**

Writing in math, how can estimating help you add two-digit numbers?

*November 15, 2010*

**Chemistry**

Name these compounds (^these are symbolize subscripts) 1. CoCl^3 2. CrF^6 3. AgBr 4. Fe^20^3 5. CrF^3 6. TiCl^4

*November 15, 2010*

**Physics help**

A 1.0 kg object is suspended from a vertical spring whose spring constant is 105 N/m. The object is pulled straight down by an additional distance of 0.25 m and released from rest. Find the speed with which the object passes through its original position on the way up.

*November 15, 2010*

**Algebra 1**

o ok thank you

*November 14, 2010*

**Algebra 1**

write a function rule for each situation. The volume V(n) of a cube when you know the length n of a side.

*November 14, 2010*

**Chemistry**

Why do magnesium, phosphorus, and zinc exhibit slightly higher first ionization energies than the general trend within each of their periods?

*November 10, 2010*

**Chemistry Honors**

Hello, Can you please tell me how a fisher chart differs from a traditional chart?

*November 10, 2010*

**CHEMISTRY**

Hello, Can you please tell me how a fisher chart differs from a traditional chart?

*November 10, 2010*

**physics help**

A 5.00 kg ball (ball 1), moving to the right at a velocity of +4.00 m/s on a frictionless table, collides head-on with a stationary 7.60 kg ball (ball 2). Find the final velocities of the balls if the collision is as specified below. (a) elastic collision ball 1 ball 2 (b) ...

*November 9, 2010*

**economics (game theory)**

Consider the normal tick tack toe game, but this time you have to AVOID getting 3 in a row in any line. Is there any strategy you can tell me that will make sure the first mover doesnt lose. Thanks

*November 9, 2010*

**physics**

Water is flowing at 6 m/s in a circular pipe. If the diameter of the pipe decreases to five-seventh its former value, what is the velocity of the water downstream?

*November 8, 2010*

**chemistry**

predict the order of increasing acidity of the compounds. Give a brief explanation why. Butanoic acid-Nexanoic acid-Benzoic acid-Acetic acid. thx

*November 6, 2010*

**English**

which of the following words cannot use the suffix -ive? reveal- decis- conclus- impress-

*November 5, 2010*

**chemistry**

Can you tell me the geometry(around the carbon/oxygen atom) and whether this is polar or non polar CH3CH3? thx

*November 3, 2010*

**chemistry**

i need 2 lewis dot structures for C3H8O. thanks

*November 3, 2010*