Science & Mathematics - 28 November 2007

Iodine-131 is a beta emitter with a half-life of 8.070 days that is used to treat thydroid cancer. How many days are required to rid the body of 71.0% of any ingested I-131?

2007-11-28 07:33:44 · 1 answers · asked by Nick P 1 in Chemistry

2007-11-28 07:29:53 · 2 answers · asked by Anonymous in Biology

is this a good stargazing tool for a family? im wondering if my ten year old son would benefit from it. he alreayd has a telescope.

2007-11-28 07:29:51 · 4 answers · asked by Anonymous in Astronomy & Space

Evaluate Please:

Log Base 9 (9*sqrt 3)

Here are my answer choices, please make sure to tell me how you arrived at this answer or it does me absolutely no good. Thanks!

a) -5/2
b) 5/2
c) -5
d) 4
e) 2

2007-11-28 07:25:52 · 6 answers · asked by Flauta 2 in Mathematics

what does it stand for

2007-11-28 07:25:09 · 4 answers · asked by Anonymous in Biology

2007-11-28 07:24:50 · 4 answers · asked by Anonymous in Mathematics

2007-11-28 07:24:14 · 2 answers · asked by Anonymous in Engineering

2007-11-28 07:23:21 · 4 answers · asked by Anonymous in Biology

2007-11-28 07:22:17 · 8 answers · asked by smileyD 1 in Mathematics

4x + 1 = 21 and 3x-3=18

2007-11-28 07:22:09 · 26 answers · asked by pussicus911 2 in Mathematics

how does 5/12pi = cos( pi/6 + pi/4)????

2007-11-28 07:19:57 · 3 answers · asked by Anonymous in Mathematics

Hi can anyone tell me what AND-OR gates are plz?

thnx in advance

2007-11-28 07:14:08 · 11 answers · asked by Danielle 3 in Engineering

2007-11-28 07:13:48 · 4 answers · asked by smileyD 1 in Mathematics

I believe so.

2007-11-28 07:13:45 · 14 answers · asked by Jason S 2 in Astronomy & Space

OK....here goes the foolish question of the day. ;0)
82 divided by 8. Why do we not divide into the 8 and skip right to the 82? 8 can go into 8 right??? The answer does not come out right though it you divide into 8 first ( such as if the equation was 92 divided by 8 ....you would divide into the 9 first then bring down the 2 etc. to get the correct answer ). My son asked me this as a homework question. Help?! Thank you in advance for your assistance.

2007-11-28 07:13:28 · 7 answers · asked by Kim M 1 in Mathematics

2007-11-28 07:12:30 · 3 answers · asked by Anonymous in Mathematics

A cylinder contains 270 L of hydrogen gas (H2 at 0.0° C) and a pressure of 10 atm. How much energy is required to raise the temperature of this gas to 25°C?

2007-11-28 07:11:39 · 2 answers · asked by Jerry M 1 in Physics

A ball player hits a home run, and the baseball just clears a wall 8.00 m high located 106.7 m from home plate. The ball is hit at an angle of 36.2 degrees to the horizontal, and air resistance is negligible. Assume the ball is hit at a height of 1.1 m above the ground. What is the initial speed of the ball in m/s?

2007-11-28 07:11:26 · 2 answers · asked by Anonymous in Engineering

I need the right answer to this problem 3/x2 = 125. Show me how you got your answer please. Thank You

2007-11-28 07:09:31 · 2 answers · asked by Hugh B 1 in Mathematics

please explain how you got the answer:

Convert the rectangular coordinates to polar coordinates with r>0 and with theta between 0 and 2pi.

(3squareroot3, -3)

2007-11-28 07:09:27 · 3 answers · asked by Anonymous in Mathematics

2007-11-28 07:03:48 · 4 answers · asked by spicymnguy 5 in Earth Sciences & Geology

In logic gates, if it is said that AND/OR gates exhibit duality, what exactly do they mean? and how about applying duality to gates? what does that mean plz? thnx so much guyz!!

2007-11-28 07:03:13 · 2 answers · asked by Danielle 3 in Engineering

I was in a car wreck & knocked out for awhile...but I don't remember anything happening with my spirit. Yet, some say that people in a coma have their spirit travel outside their body. (just trying to understand this)

2007-11-28 07:01:54 · 8 answers · asked by Deenie 6 in Paranormal Phenomena

4. You measure a distance from diffraction to screen to be 285[mm]. What should be the angle to the first spot measured off axis, if the distance from the center spot is 1.204E+02[mm]?
angle = __________________ [degree]
Use three significant figures or N/A, if not enough information is given.


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5. What is the previous answer in radian?
angle = _____________[radian]
Use three significant figures or N/A, if not enough information is given.

PLEASE HELP AND EXPLAIN STEP BY STEP THANKS, HAVING A HARD TIME!!

2007-11-28 06:59:51 · 1 answers · asked by Anonymous in Physics

My price range is $400-500 i want to be able to see the rings on saturn and the red spot on juipiter and the ice caps on mars but i don't think a 500 telescope can see all that. But if im wrong tell me.

2007-11-28 06:59:10 · 8 answers · asked by jason h 1 in Astronomy & Space

if cellulose is a hydrophilic substance how come that palnts cell wall is not soluble ???

2007-11-28 06:54:58 · 2 answers · asked by jo n jo 5 in Botany

2007-11-28 06:54:21 · 1 answers · asked by Anonymous in Biology

x^2 + y^2 - 4x - 6y - 12 = 0

find the centre and radius of the circle

2007-11-28 06:53:50 · 3 answers · asked by Anonymous in Mathematics

2007-11-28 06:50:57 · 9 answers · asked by Anonymous in Chemistry

my answer is -3,7

2007-11-28 06:50:24 · 7 answers · asked by thonia 1 in Mathematics