Science & Mathematics - 9 December 2007

Here is the problem...I'm not asking you to do it for me, I just really need a simple expanation of the formulas used to solve it.

Suppose a family has 5 children. Also, suppose that the probability of having a girl is 1/2. Find the probability requested.

1. two girls and three boys
2.no girls
3. three girls and two boys
4.four girls
5.three boys

2007-12-09 16:32:34 · 8 answers · asked by Curious_J 3 in Mathematics

which is larger in atomic radius? Nitrogen or Boron and why?
which is larger in ionic radius? Rb+ or Br- and why?
which is larger in electronegativity? Oxygen or Sulfur and why?

i dont get trends at all :[
help
thanks!

2007-12-09 16:32:33 · 1 answers · asked by shynhuggable 3 in Chemistry

evaluate

2007-12-09 16:29:02 · 6 answers · asked by thonia 1 in Mathematics

Seems like you're always on here. I can see pd doesn't...but most others of you have closed profiles. Just wondered.....I'm thinking about visiting the Science section. Will I be welcomed over there?

2007-12-09 16:27:46 · 15 answers · asked by Deenie 6 in Paranormal Phenomena

2007-12-09 16:25:05 · 10 answers · asked by Anonymous in Astronomy & Space

3x + 2y + z = 9
3 - 4y - z = 5
5x + y + 3z = 24

2007-12-09 16:22:58 · 5 answers · asked by Anonymous in Mathematics

1)Ann walks 5km in 1 hour,and betty walks 4km in 1 hour.If they start walking toward each other fom a distrance of 36km,How many hours willl it take for them to meet?
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2)Denny walks 60 m in 1 minute,and john travels 210 m in 1 minute by bike.
if denny has already walked 1800 m,how many minutes will it tkae for john to catch up with denny by bike assuming denny continues to walk?

Please show in steps.....

2007-12-09 16:21:05 · 12 answers · asked by Tommy 1 in Mathematics

is This slope -6/-8 parallel to 6/8?

2007-12-09 16:18:05 · 5 answers · asked by Anonymous in Mathematics

Can someone explain them to me in English? My textbook is confusing. I'm Honors Alg 2 level, so just the basic ones.

2007-12-09 16:17:45 · 3 answers · asked by Anonymous in Mathematics

How would rotation help an object as it falls? Why is it helpful to do this? What about torque?

2007-12-09 16:17:25 · 1 answers · asked by monkey_king122 2 in Physics

2007-12-09 16:15:19 · 8 answers · asked by :) 2 in Mathematics

I have heard different views about it. Some people investigate alledged hauntings and seem to be perfectly fine...while others have gotten themselves into deeper water by accidentally attracting evil spirits...many times in which can inhabit the investigator's home or taunt them or their families. How dangerous is it really to be a paranormal investigator? Just curious...

2007-12-09 16:13:52 · 21 answers · asked by *Tessie* 3 in Paranormal Phenomena

This queastion is fom my science project it said to recrod my daily log and under it in perhantesees () it said dated journal enteries documenting all progress.what does this meen

2007-12-09 16:02:27 · 3 answers · asked by Anonymous in Other - Science

Is it because the vector created by the 2 bromines cancel the vector of the 2 lone pairs? If so, how can this be? Isn't the vector created by the lone pairs 'stronger' than the vector created by the 2 bromines?

2007-12-09 16:01:56 · 7 answers · asked by Anonymous in Chemistry

2007-12-09 16:01:28 · 1 answers · asked by Anonymous in Chemistry

any help would be great!

2007-12-09 15:56:16 · 7 answers · asked by Anonymous in Other - Science

given this formula

C6H12 (l) + 9 (O2) (g) ---> 6 (CO2) (g) + 6 (H2O) (l)
and that the heat of formation for C6H12 is -151.9 kj/mol

find the work done, how do you do this

2007-12-09 15:53:49 · 2 answers · asked by abrakadabra a 1 in Chemistry

The solid bounded by x^2+y^2=1, z=sqt(x^2+y^2), z=0.
Represent a cylinder extending along the z- axis and a cone above the z-axis, respectively.
Any ideas??
Thanks in advance!

2007-12-09 15:50:02 · 1 answers · asked by Anonymous in Mathematics

i asked a question like this earlier only this time its

Sin^-1 (-1/2)

how would you go about solving this? what does the negative attached to the sine mean? Thanks in advance

2007-12-09 15:43:03 · 6 answers · asked by Fabregas 4 in Mathematics

parallel universe or Multiverse is the concept of Quantum physics these days, does anyone of u believe it? and can anyone explain more about it?

2007-12-09 15:41:37 · 28 answers · asked by Anonymous in Physics

At which point(s) does the mass on a vibrating spring have its largest velocity? Smallest velocity?


Or if anyone knows the answer to either of these questions, much appreciated as well. Our physics teacher isn't the best at explaining things.

If the amplitude of the vibration of the spring is doubled, what happens to the period?

If a stiffer spring were used so that the spring constant were 4 times as great, how would the frequency and period be affected?

2007-12-09 15:40:52 · 1 answers · asked by Anonymous in Physics

Hi, please explain how to do this problem. I don't understand how to do this at all and it would be appreciated if you would explain this to me. I need to simplify the square roots as much as possible. Thanks ^^

2007-12-09 15:32:41 · 4 answers · asked by :) 2 in Mathematics

A 20.0mg sample of protien is dissolved in water to make 25.0ml of solution. The osmotic pressure of the solution is .56mmHg at 25C. What is the molar mass of proteien?

I really need help on this please guys

thanks

2007-12-09 15:24:05 · 2 answers · asked by Anonymous in Chemistry

2007-12-09 15:22:58 · 3 answers · asked by Anonymous in Medicine

Suppose that you start with a charge of 0.002 C, and find that it takes 24 J of work to move it from point A to point B. Now what is the voltage difference between points A and B?

If this charge is release, what will be its kinetic energy as it flies back past point A?

2007-12-09 15:22:26 · 2 answers · asked by Anonymous in Physics

I'm stuck on my hw which is due tomorow. It's chemistry and it's giving me differents substances like CO2 and oxygen and hydrogen. I just need the formula to convert litres into grams. Thank you for your help.

2007-12-09 15:21:09 · 4 answers · asked by Jennifer N 1 in Chemistry

You are not harmed by contact with a charged balloon, even though its voltage is very high. Is the reason for this similar to why you are not harmed by the greater than 1000 degrees C sparks from a Fourth of July sparkler?

2007-12-09 15:20:07 · 1 answers · asked by Anonymous in Physics

I'm doing a review and this one has me stuck. If someone could break it down for me and give me the answer, and tell me how they got it, you will get many points and much respect. Please and thank you.

-- The complete burning of Ethane, C2H6, produces CO2 and water vapor as its only products. Assume all substances are gases measured at the same temperature and pressure. How many liters of Ethane and Oxygen would produce 7.07 L of CO2?

2007-12-09 15:19:38 · 2 answers · asked by Anonymous in Chemistry

2007-12-09 15:16:42 · 3 answers · asked by Anonymous in Biology

WHAT IS THE LARGEST MAN MADE STRUCTURE ON EARTH?

2007-12-09 15:15:19 · 61 answers · asked by Anonymous in Astronomy & Space