# Posts by David

Total # Posts: 2,249

**chemistry**

i need 2 lewis dot structures for C3H8O. thanks

*November 3, 2010*

**Science**

What do engineers do?

*November 3, 2010*

**science**

o ok thank u

*November 2, 2010*

**science**

Yes,I'm asking for habitat niches. the island was devastated by volcanic activity.

*November 2, 2010*

**science**

Why are so much niches available on so much recently devastated islands?

*November 2, 2010*

**Algebra**

Factorise completely: 6x^2+10x-5= and 6x^2+8x-3=

*November 2, 2010*

**8th grade**

thank you

*November 1, 2010*

**8th grade**

how do seed banks preserve seeds for future generations?

*November 1, 2010*

**chem.**

CH3COOH + C5H12O -> C7H14O2 + H2O If the yield for the reaction is 45%, how many grams of the product are formed when 3.58 g of acetic acid are reacted with 4.75 grams of isopentyl alcohol? Millimoles of acetic acid= 59.6667 Millimoles of isopentyl alcohol= 53.9773 How ...

*November 1, 2010*

**Chemistry**

CH3COOH + C5H12O -> C7H14O2 + H2O If the yield for the reaction is 45%, how many grams of the product are formed when 3.58 g of acetic acid are reacted with 4.75 grams of isopentyl alcohol? Millimoles of acetic acid= 59.6667 Millimoles of isopentyl alcohol= 53.9773 How ...

*November 1, 2010*

**physics**

A 280 N force is pulling an 80.0 kg refrigerator across a horizontal surface. The force acts at an angle of 18.0° above the surface. The coefficient of kinetic friction is 0.200, and the refrigerator moves a distance of 8.00 m. (a) Find the work done by the pulling force...

*October 28, 2010*

**math**

How do I take the derivative in respect to c1 for the following utility function? u1 = log(c1) + log [1/2(x-c1-c2)] details please

*October 26, 2010*

**math**

How do I take the derivative in respect to c1 for the following utility function? u1 = log(c1) + log [1/2(x-c1-c2)] details please

*October 25, 2010*

**Physics**

Two identical cars are traveling at the same speed. One is heading due east and the other due north, as the drawing show. What is true regarding the kinetic energies and momenta of the cars?

*October 24, 2010*

**Physics**

The equation here is -8.4=.145(-32+V)

*October 24, 2010*

**O Chem**

I need help with this question please. Draw the structure of triacylglycerol formed from oleic acid, linoleic acid, and stearic acid. Give balanced equation and show how much hydrogen would be needed to reduce the triacylglycerol completely, show the product.

*October 19, 2010*

**8th grade**

you should do the work you bum rather then go and go find the answers

*October 14, 2010*

**Chemistry**

what's the answer?

*October 11, 2010*

**intro to chemistry**

A sample of nitrogen has a volume of 50.0L at a pressure of 760mmHg. What is the volume of the gas at each of the following pressures if there is no change in temperature? A. 1500mmHg B. 2.0atm C. 0.500atm

*October 11, 2010*

**intro to chemistry**

The air in a 5.00L tank has a pressure of 1.20atm. What is the new pressure of the air when the air is placed in tanks that have the following volumes, if there is no change in temperature? A. 1.00L B. 2500ml C. 750ml

*October 11, 2010*

**Statistics**

any help?

*October 10, 2010*

**Statistics**

A superstore manager wishes to give out a survey to a sample of 25 of its workers. It wants the sample to be a good representation of the workers. The table shows the numbers of workers in each section of the work force: Working tills: 32 Stacking shelves: 24 Office/managers: ...

*October 10, 2010*

**statistics**

Could you rephrase that please, I'm not getting the logic.

*October 10, 2010*

**statistics**

any help?

*October 10, 2010*

**statistics**

There are 50 members. Melvin wants to collect some infromation from seven of them. Explain how he can do this using the following set of random numbers: 86, 13, 84, 10, 07, 30, 39, 65, 97, 96, 88, 12, 39, 26, 04, 89

*October 10, 2010*

**Algebra I**

A rectangle has a width of 6x+7, a length of 13 How do I get the area?

*October 7, 2010*

**science**

More oxygen will ___________ in colder water than in warmer water.

*October 7, 2010*

**Physics**

In a cyclotron (one type of particle accelerator), a deuteron (of mass 2.00 u) reaches a final speed of 8.4% of the speed of light while moving in a circular path of radius 0.551 m. What magnitude of magnetic force is required to maintain the deuteron in a circular path?

*October 5, 2010*

**Chemistry**

Oh thank you!

*October 4, 2010*

**Chemistry**

so did I do it right?

*October 4, 2010*

**Chemistry**

A graduated cylinder massed at 34.56g and then 8.6 ml was added of an unkonwn liquid this brought the mass to 45.87g. What is the density? I'm not sure how to go about this. Is the 34.56g unneccessary information? Or, do you subtract 45.87-34.56= 11.31 then do mass 11.31/...

*October 4, 2010*

**medical terminology**

which of the following is an example of a symptom?

*September 29, 2010*

**science**

microscope lens used to locate the specimen

*September 28, 2010*

**Biology**

not helping !

*September 23, 2010*

**Biology**

Eggs of Amphioxus is : (a)alecithal (b)telolecithal (c)meiolecithal (d)mesolecithal is it A ?

*September 23, 2010*

**Biology**

Human cell

*September 23, 2010*

**Chemistry**

the water will freeze

*September 20, 2010*

**Algebra**

A certain can of iced tea contains 4% of the recommended daily allowance of sodium. The recommended daily allowance is 2500 milligrams. How many milligrams of sodium are in the can of iced tea?

*September 20, 2010*

**10th grade**

A rational number is ____ a real number. a. always b. never c. sometimes its always ???????

*September 20, 2010*

**personal finance concepts**

Donna and Sherman Terrel are preparing a budget for 2010. Donna is a systems analyst with an airplane manufacturer, and Sherman is working on a master's degree in educational psychology. The Terrels do not have any children or other dependents. Donna estimates her salary ...

*September 20, 2010*

**Math**

Hi - there are any number of them, but they're all infinite series: if you go to Wikipedia and look up "pi", you'll find at least fifteen of them in the "Computation in the Computer Age" section of that entry.

*September 19, 2010*

**criminal justice**

Follow Bob Pursley's link on the difference between Morals and Ethics in his response to "Ilisa" a little further down this list: it'll give you some help in at least defining the problem, if not some help answering it.

*September 19, 2010*

**Statistics**

a - either you've just seen something that's phenomenally unlikely, or the coin's owner isn't being truthful about the fairness of the coin. b - you've just seen something that's consistent with the coin's owner's pronouncement that the coin is ...

*September 19, 2010*

**Statistics**

The first thing you need is a random selection of graduates whose salaries can be compared... and that's probably the trickiest bit, because getting a genuinely random selection of graduates could more difficult than you might think. Suppose for example your subject is ...

*September 19, 2010*

**math**

Oops: I've got the last bit of the explanation of c) incorrect, but I'm sure you can correct it.

*September 19, 2010*

**math**

What fun! a) You can cancel out numbers that are common to the top and bottom of a fraction... but you can't cancel individual digits! b) These examples suggest that a/b + c/d = (a+c)/(b+d). Wrong! c) These examples suggest that {a+(b/c)} - {d+(e/f)} = {(a-d) + (b-e)/(f-d...

*September 19, 2010*

**U.S. Government**

A depressing, but no doubt accurate explanation. We have a similar system over here in the UK: it's been either "Heightened" or "Extreme" for as long as I've been aware of it - and now that you've spelt it out, I realise I'd actually assume ...

*September 18, 2010*

**math**

This has been posted elsewhere, and is answered there.

*September 18, 2010*

**math**

This has been posted elsewhere, and is answered there.

*September 18, 2010*

**math**

Do you mean how many separate pairings exist between two groups of objects, each of which contains eight elements? If so, the answer is (8 x 8) = 64. The reason I'm slightly cautious about the answer is that I'd have expected the second part of the question to be ...

*September 17, 2010*

**PHI103: Informal Logic**

I'll have a go at just the first one, because I think it illustrates a point that's worth making. Forget the multiple-choice options for a moment: concentrate on the original statement, which when you rephrase it slightly asserts that the only overdues at the store are...

*September 17, 2010*

**math**

What is the actual question please?

*September 17, 2010*

**alegebra**

Divide any whole number by any other whole number that isn't a factor of it. For example, try dividing 3 by 2. Is the result a whole number?

*September 17, 2010*

**Algebra**

A vehicle uses 1 tablespoon of gasoline to drive 125 yards. How many miles can the vehicle travel per gallon? Round your answer to the nearest mile. (hint: There are 256 tablespoons in a gallon)

*September 16, 2010*

**Physics Flux**

The electric flux through the surface shown in Figure Ex27.10 is 15.0 Nm2/C, and the electric field makes an angle á = 70° with the surface. What is the electric field strength? The surface is a 10cm by 10cm square.

*September 13, 2010*

**science**

ops! b.the science of patterns and relationships

*September 12, 2010*

**science**

c.the science of numbers .???????

*September 12, 2010*

**science**

What is the definition of Mathematics? a.adding and subtracting numbers b.the science of patterns and relationships c.the science of numbers d.a really hard subject

*September 12, 2010*

**science**

????? Please help

*September 12, 2010*

**science**

Which shows the expression below simplified? (3.6 × 10^15) + (1.8 × 10^12) a. 3.60018 × 10^15 b. 3.902 × 10^14 c. 3.618 × 10^15 d. 3.6018 × 10^15

*September 12, 2010*

**9gr**

impossible

*September 12, 2010*

**8th Grade Algebra**

Ok. I wa thinking that! Thank you!

*September 9, 2010*

**8th Grade Algebra**

I think that... 3m - 10 = 2(4m-5) 3m - 10 = 8m - 10 +10 on both sides but the thing is, I'm stumped when i get... 3m = 8m I don't think this is possible but I'm thinknig I'm doing something wrong here so that's why I posted.

*September 9, 2010*

**8th Grade Algebra**

3m - 10 = 2(4m -5)

*September 9, 2010*

**9gr**

1. At 11:00 a.m. a one-meter-high mailbox casts a 0.7-meter shadow. If a pole beside the mailbox casts a 28-meter shadow, how tall is that pole? 400 m 40 m 0.4 m 4 m

*September 9, 2010*

**9th grade**

4g

*September 9, 2010*

**9th grade**

Write an algebraic expression for the phrase. the product of g and 4 a.4g b.g + 4 c.g/4 d.g – 4

*September 9, 2010*

**9 gr**

Write each product in exponential form. 16 × 16 × 16 × 16 × 16 a.5^16 b.16^5 c.16^6 d.16^4 my answer 16^5

*September 9, 2010*

**10th grade**

5x5x5x5=5^4

*September 9, 2010*

**Algebra**

3m - 10 = 2(4m -5)

*September 9, 2010*

**Science**

An airplane flew a distance of 650 km at an average speed of 300km/h. How much time did the flight take?

*September 8, 2010*

**physics**

A truck is stopped at a stoplight. When the light turns green, it accelerates at 2.9 m/s2. At the same instant, a car passes the truck going 12 m/s. Where and when does the truck catch up with the car?

*September 7, 2010*

**physics**

A bike accelerates from 0.0 m/s to 4.1 m/s in 6 s. What distance does it travel? thanks for the help

*September 7, 2010*

**physics**

A bike accelerates from 0.0 m/s to 4.1 m/s in 6 s. What distance does it travel? thanks for the help

*September 7, 2010*

**Algebra**

Sorry I forgot to put in the answer. It's 2d +1/5 = 3/5

*September 7, 2010*

**Algebra**

2d + 1 fifth

*September 7, 2010*

**5th Grade Math**

I'm putting the answer on the right because that's how I'm used to it. so... (3*0.1) + (X) = 0.38 First we do the problems in parentheses. Since we are looking to find X we are not going to do that right now. (3*0.1) = 0.3. Now we subtract that from the equation. 0...

*September 7, 2010*

**Algebra**

this is 2d + 1 fifth. Sorry the formatting for this problem is incorrect.

*September 7, 2010*

**Algebra**

2d + 1 --- 5

*September 7, 2010*

**MATH**

11 hotdogs

*September 5, 2010*

**Physics**

3 There are two charges +Q and –Q/2 that locate at two positions with a separation of d as shown in Fig. 1. We may put +Q at the origin of the x-axis to facilitate the calculation. (a) Find the electric field for +Q and –Q/2 at the position P. (5 points) (b) What is ...

*September 5, 2010*

**Physics**

The figure below shows two pint charges, each of -2Q, fixed on the y-axis at y = +a and at y = -a . A third points charge -Q is placed on the x-axis at x = 2a . Express all algebraic answers in terms of Q, a, and fundamental constants. (a) What is the net force (magnitude and ...

*September 5, 2010*

**math**

Find the standard deviation for the data. Round your answer to one more decimal place than the original data. {15,13,31,42,58,78}

*September 3, 2010*

**Finance**

7,200 at 10% and 4,800 at 15%.

*September 3, 2010*

**Math**

( -4 ) 3 (----) ( 5 ) if you can't read that, negative 4, fifths, squared. -4/5 in parentheses.

*August 31, 2010*

**G.A**

What is the answer to the brainteaser NOMMAG

*August 28, 2010*

**Chemistry**

What is the freezing point of an aqueous 2.65 m calcium chloride (CaCl2) solution? The freezing point of pure water is 0.0ºC and Kf of pure water is -1.86ºC/m.

*August 21, 2010*

**Algebra**

So, I'm thinking based on the sites you given that... body temperature = rational number money owed = rational number home runs = whole numbers Is this correct?

*August 21, 2010*

**Algebra**

I have some understanding of this but not quite sure how to do the problem. Direction & problem below. Direction: Tell whether whole numbers, integers, or rational numbers are the most reasonable to describe each. Explain your answer. Problem: body temperature; money owed; ...

*August 21, 2010*

**statistics**

4343

*August 17, 2010*

**Algebra**

Abby has four times as many pictures as Sally. Abby had 18 more pictures than Sally. How many pictures did each girl have?

*August 11, 2010*

**Algebra**

Bill has 12 more than three times the number of baseball cards Chyris has. Bill has 42 cards more than Chris. How many baseball cards does Chris have?

*August 11, 2010*

**Algebra**

Thank You Henry

*August 11, 2010*

**Algebra**

Randy, Sam, Tim and Will counted the number of puzzles they had solved in two months. Sam has solved twelve more than Tim. Randy had solved seventeen less than Sam.Will had solved twice as many as Randy. They have solved a total of 267 problems. How many puzzles did each ...

*August 11, 2010*

**algebra**

6/7s-3/4=4/5-1/7s+1/6

*July 29, 2010*

**math**

6/7s-3/4=4/5-1/7s+1/6

*July 29, 2010*

**Physics (Static Friction)**

When you take your 1300-kg car out for a spin, you go around a corner of radius 56.9 m with a speed of 15.8 m/s. The coefficient of static friction between the car and the road is 0.75. Assuming your car doesn't skid, what is the force exerted on it by static friction? I ...

*July 28, 2010*

**C++ Programming**

I already know how to use Visual C++ Express but I;m having a problem that I can not figure out. So, my problem is below. I go into Skript.rc Push F7 to build the RC script first. Output says... Fatal error RC1015: cannot open include file 'afxres.h' Other sources tell...

*July 28, 2010*

**C++ Programming**

Hello. I use Visual C++ 2010 Express and don't know why this is occuring. I go into Skript.rc Push F7 to build the RC script first. Output says... Fatal error RC1015: cannot open include file 'afxres.h' Other sources tell me to replace it with windows.h but then it...

*July 28, 2010*

**Chemistry**

A compound on heating gives a crackling sound, a reddish fume, and a gas which relights a glowing splint. the residue is reddish brown when hot and yellow when cold. What are- 1. the compound? 2. the fume 3. the gas 4. the residue?

*July 27, 2010*