Science & Mathematics - 24 July 2007

At about 9:48pm or so today (7-24-07) my sister, her friends, my parents and I saw this bright flash in the sky. It lit up half of the sky. At about the same time, my brother told me that the lights had gone off in his room. Weird huh? I came across this article from 7-24-01 where these things happened too, the flash in the sky and electricity going out, it ended being that a meteor exploded in the air, but no one knows if this was something relevant to that....if you saw or know anything post it. let me know.

2007-07-24 18:48:37 · 7 answers · asked by Lucy C 1 in Astronomy & Space

in the scientific notation 4.140625 x 10^-3
the 10 with the exponent should equal .001 to come out to the right answer. (.004140625) but 10^-3 equals .01 when i figure it out. (10 divided by 1000). the rules for scientific notation say that the exponent describes a move of the decimal point. so negative 3 would be three to the left. and that is correct, by why does 10^-3 work out to .01 when i do the math for the 10 and the exponent only? the notation doesn't seem to make sense to me.... please help!!!!!!!!!!!

2007-07-24 18:43:31 · 3 answers · asked by Anonymous in Mathematics

test how you can give best information in the least time

afterall time is money

value it & be fast, short &simple

2007-07-24 18:42:48 · 14 answers · asked by Anonymous in Biology

2007-07-24 18:34:18 · 5 answers · asked by LoveMachine 1 in Zoology

6.91 grams of N2, 4.71 grams of O2 and 2.95 G of He
Please show me how you did this as I did this and totaled up everything and my answer isn't jiving w/ the back of the book.
TY

2007-07-24 18:30:51 · 4 answers · asked by susanstudio2000 1 in Chemistry

2007-07-24 18:28:14 · 6 answers · asked by Anonymous in Mathematics

2007-07-24 18:27:26 · 4 answers · asked by Anonymous in Mathematics

I borrowed $4000 and after few days I again borrowed $2000 .When the other person asked me for the money
Question Details: I said
,
" the sum of 4000 and 2000 is equal to zero, so I do
not have
any balance to pay".

and i explained it with the algebric formulae " let a = 4000, b = 2000 and c = 6000"
a + b = c
Multiply both sides by a + b
=> (a + b) (a + b) = c (a + b)
=> a*a + ab + ba + b*b = ca + cb
=> a*a + ab - ca = cb - b*b - ba
=> a( a + b -c) = -b(b + a - c)
so a = -b
=> a + b = 0

Can some one pls chk if the solved problem is wrong or intimate me where i have made a mistake

2007-07-24 18:20:26 · 11 answers · asked by boss 1 in Mathematics

2Al + 3Br2→ 2AlBr3

AlBr3 is reduced and Br2 is oxidized.
Al is reduced and Br2 is oxidized.
Al is oxidized and Br2 is reduced.
AlBr3 is oxidized and Al is reduced.
AlBr3 is reduced and Al is oxidized.

2007-07-24 18:13:17 · 1 answers · asked by lpatt949 1 in Chemistry

How would i answer this question?


*What would be the LD50 for a body mass of 100 lbs? (4.07g/kg)

2007-07-24 18:12:30 · 1 answers · asked by baby_princess_melissa 2 in Chemistry

Felis domestica
Felis Domestica
felis domestica
Felis domestica
felis Domestica

2}The Hardy-Weinberg formula

is useful in determining the extent to which a sexually reproducing population is evolving.
is used to predict when genetic drift will occur in a sexually reproducing population
is useful in determining the extent to which polyploidy is occurring in specific plant populations.
is used to predict when specific groups of organisms will become extinct.
all of these answers are correct.

2007-07-24 18:12:26 · 1 answers · asked by Anonymous in Botany

2007-07-24 18:11:09 · 9 answers · asked by Gbinz 3 in Mathematics

Some days its hotter than heck and when the Sun goes down its almost freezing. That heat energy seems to be gone, but where did it go.

2007-07-24 18:11:06 · 9 answers · asked by barry_smith_12357 2 in Weather

2007-07-24 18:04:42 · 6 answers · asked by harish p 2 in Engineering

In finding the distance between two points P1(x1,y1) and P2 (x2,y2), the most direct procedure is to use what formula?

2007-07-24 18:01:03 · 8 answers · asked by WiganRedskins 1 in Mathematics

2007-07-24 17:59:54 · 10 answers · asked by selva 1 in Astronomy & Space

2007-07-24 17:59:54 · 1 answers · asked by Krys. 1 in Botany

Please help me. I need to know the names and properties of these 3 types of carbon-oxygen molecules.
Please try to answer as simply as possible because I am not very intelligent :P

I would really appreciate it if useful links are included.

2007-07-24 17:57:31 · 2 answers · asked by Anonymous in Chemistry

2007-07-24 17:54:28 · 2 answers · asked by brent d 1 in Geography

if u could put the whole internet on a scale how much do u think it would weigh? *how much do u think the whole internet weighs*

2007-07-24 17:54:20 · 8 answers · asked by Luke 3 in Other - Science

2007-07-24 17:53:45 · 3 answers · asked by dolphin_lover 1 in Zoology

LD(subsript) 50?

2007-07-24 17:52:54 · 10 answers · asked by baby_princess_melissa 2 in Chemistry

Gaseous Mixture has 6.91g of N2, 4.71g of O2, and 2.95g of He. What volume does this mixture occupy @ 28C and 1.05 atm pressure? Please show me how you got this answer. I am thinking I need to convert the grams to moles? Thank you!

2007-07-24 17:50:59 · 1 answers · asked by susanstudio2000 1 in Chemistry

Also how can I know that it can compensate for the air lost that comes out from under the skirt?

2007-07-24 17:47:40 · 2 answers · asked by Anonymous in Engineering

i am always asked "which came first the chicken or the egg"but i never know have like scientists found out yet???

2007-07-24 17:43:48 · 34 answers · asked by philisity_scatcat 2 in Biology

2007-07-24 17:36:25 · 7 answers · asked by Kara 2 in Astronomy & Space

A long straight wire lies on a horizontal table and carries an ever increasing current northward. Two coils of wire lie flat on the table, one on either side of the wire. When viewed from above, the induced current circles:

a)counterclockwise in both coils
b)clockwise in both coils
c)clockwise in the east coil and counterclockwise in the west coil
d)clockwise in the west coil and counter clockwise in the east coil

WHAT??? i have no clue what this means! please help

2007-07-24 17:36:25 · 3 answers · asked by Kel 1 in Physics

2007-07-24 17:34:32 · 5 answers · asked by triggrhappy0 2 in Physics

2007-07-24 17:34:28 · 6 answers · asked by Anonymous in Mathematics

I'm doing an experiment where I am growing 10 radish seeds each in 5 germination bags (plastic bags) with each lined with Paper Towel. There has to be 5 levels of the independent variable and I chose the pH level of the water on the paper towels. But how do you get different pH levels of the water? The control will be the bag with water with a pH level of 7.

2007-07-24 17:33:19 · 4 answers · asked by Anonymous in Botany