Science & Mathematics - 28 October 2007

Solve it. I got 1.70 (rounded)
Correct?
You round 5's down, right? I can never remember...

2007-10-28 14:41:28 · 5 answers · asked by Anonymous in Mathematics

Do organic compunds contain carbon, hydrogen and oxygen or just carbon and hydrogen?

Why? please i need help!

~THANK YOU!!

2007-10-28 14:40:40 · 2 answers · asked by Mina 1 in Biology

How would i build a jet engine comparable to this one?

http://youtube.com/watch?v=krAzGMxAIl8

what components are needed?

2007-10-28 14:40:38 · 4 answers · asked by dreamliner787 1 in Engineering

a tennis ball is thrown vertically upward with an initial velocity of +8.0 m/s
A)what will the balls speed be when it reaches its starting point
B)how long will the ball take to reach its starting point

please solve and show your work, i would like to understand how this problem works as it is the only one in the section that i don't understand

2007-10-28 14:39:34 · 3 answers · asked by Anonymous in Physics

The container is filled with water to level h. What is the volume of water in the container (in terms of h and a)?
What is the area of the surface of the water when filled to level h (in terms of h and a)?
The water is evaporating from the container at a rate proportionate to the surface area, with proportionality constant k. Approximate the time t in which the water level drops from to level h (in terms of h, Δh, a, and k). Assume that Δh is small, and that the rate doesn’t change much during this time.
If the water is initially filled to level H, how long will it take to completely evaporate?
I need to show all my work thanks

2007-10-28 14:39:24 · 2 answers · asked by ironmanfb12 1 in Physics

With Halloween fast approaching, I was wondering if you believe in the paranormal. Why or why not?

2007-10-28 14:37:26 · 28 answers · asked by Anonymous in Paranormal Phenomena

2007-10-28 14:34:45 · 1 answers · asked by Anonymous in Mathematics

2007-10-28 14:34:35 · 1 answers · asked by Colin L 1 in Biology

2007-10-28 14:34:24 · 5 answers · asked by HP2007 1 in Mathematics

I've had three different plants over the course of the past several years. The first two died after having them only a few months. The current one (I bought it about two or three weeks ago) isn't looking to great either. I've found several websites about them, none have really helped. I put the last one in the refrigerator from late November to February (more than one site suggested this), but it never came up. I would really like to be able to grow them, and I rarely have trouble with houseplants.

2007-10-28 14:32:14 · 5 answers · asked by The Doctor 7 in Botany

Calculate the energy difference (E) for the photon absorbed when a hydrogen atom undergoes a transition from n = 1 to n = 5 for 1 mol H atoms.

2007-10-28 14:31:33 · 1 answers · asked by divastr186 2 in Chemistry

2007-10-28 14:30:54 · 7 answers · asked by Anonymous in Mathematics

Solve for x: ( | indicates absolute value)

| x^2 - 2x | = 3x - 6

2007-10-28 14:30:52 · 4 answers · asked by skinzzfan25 1 in Mathematics

Why is an oak leaf not a good specimen for inspecting with a light microscope?

Why is a wet mount slide better than a dry mount slide when a living cell is the specimen?

2007-10-28 14:30:18 · 1 answers · asked by Anonymous in Biology

2007-10-28 14:29:35 · 7 answers · asked by Anonymous in Chemistry

2007-10-28 14:26:12 · 1 answers · asked by Colin L 1 in Biology

how many of H2O i dumped will be in the cup after you scooped it from the ocean?

2007-10-28 14:24:26 · 4 answers · asked by ritushstar 1 in Physics

2007-10-28 14:23:44 · 2 answers · asked by James the Just 3 in Biology

A balloon is rising at a constant speed of 5ft/sec. A boy is cycling along a straight road at a speed of 15 ft/sec. when he passes under the balloon, it is 45 ft above him. How fast is the distance between the boy and the balloon increasing 3 seconds later?

2007-10-28 14:23:42 · 2 answers · asked by Anonymous in Physics

2007-10-28 14:23:20 · 4 answers · asked by Barbiex) 1 in Mathematics

I cannot get this one for nothing and i have read this section over and over.

Distinguish between the types of substrates available to cells for H subscript 2 S production.?

2007-10-28 14:22:39 · 1 answers · asked by Anonymous in Biology

2007-10-28 14:21:26 · 17 answers · asked by James the Just 3 in Chemistry

A bottle of wine, which was analyzed for its tritium (3H) content, was found to contain 3.20% of the tritium that was originally present when the wine was bottled. How old (in years) is the bottle of wine? (The half-life of tritium is 12.3 yr.)


and



The half-life of 131I is 8.10 day.
Calculate how much time it would take for an isolated quantity of 131I to decay by 23%.

2007-10-28 14:21:07 · 1 answers · asked by thiswasjustforphysics 3 in Chemistry

i have a 100pt chpter test tommorow and i no how to do this but my dad dosent think its right and my sister is saying its weird please help to clear it

simplify this equation
-7a+3(a-c)+5c

2007-10-28 14:20:07 · 7 answers · asked by Anonymous in Mathematics

I am stuck on a question on my biology homework and i need anybodys help. Heres the question:

# 10) Describe two or three examples of tropism in plants and explain the role of auxins in these responses.

Thanks in advance.

2007-10-28 14:18:40 · 2 answers · asked by Exodus 2 in Botany

Why do we watch the news and listen to the weather report when all they are doing is guessing anyway?

2007-10-28 14:17:28 · 3 answers · asked by Anonymous in Weather

Need help with this word problem:
Shiny lawn spheres placed on pedstals are convex mirrors. One such sphere has a diameter of 40 cm. A 12-cm robin sits in a tree 1.5 m from the sphere. Where is the image of the robin and how long is the image?

So far, I figured distance of object is 150cm, and height of object is 12cm, but I need more than that for the equations!!!

2007-10-28 14:16:57 · 2 answers · asked by Team_Balla 3 in Physics

2007-10-28 14:13:09 · 1 answers · asked by Colin L 1 in Biology

a. 15 and 15
b. 11 and 19
c. 7 and 23
d. 13 and 17

2007-10-28 14:11:56 · 6 answers · asked by Anonymous in Mathematics

Use implicit differentiation to find the slope tangent line to the curve (x^3y^4)+(10y^5)= (x^5) + 335 at the point (1,2).

The Slope M = ?

I keep getting -75/816, and it's wrong. Can anyone help?

2007-10-28 14:11:19 · 4 answers · asked by tazzerz 1 in Mathematics