Science & Mathematics - 19 September 2007

3 guys on an island sinking surrounded by paronahs. they have a raft. the maximum weight is 305lbs 1 guy wieghts 102lbs the second guy 110 lbs the 3rd guys weights 265 lbs.

They all get off the island by way of raft.

How do they do it?

2007-09-19 05:20:50 · 9 answers · asked by Anonymous in Mathematics

I know the answer.....but don't know the way of solving it......anyone who can do it, describe me thoroughly, please......if you can make me understand, your answer will be chosen as a best answer!!!!

2007-09-19 05:19:16 · 5 answers · asked by maheer_bd 1 in Mathematics

Apart from bad luck (i.e. lack of the appropriate mutations), is there a reason why photosynthesising organisms have not evolved the appropriate pigments for absorbing all the available sunlight reaching the Earth's surface? (This, of course, would make them appear black.) Is this a possible area for genetic manipulation, assuming we discover the required techniques - the creation of more photosynthetically efficient organisms?

2007-09-19 05:17:35 · 11 answers · asked by Wilf 2 in Biology

2007-09-19 05:15:53 · 10 answers · asked by Simon 3 in Zoology

last year i took trig and had to drop out and am taking it again this year but i remember i looked at this website that i can't find no but it showed me how to makethe unit circle in radians by assigning numbers to all the measures then going back and simplifying the fractions gave the radian measures but i can't remember how to do it. Does anyone know?

2007-09-19 05:14:31 · 3 answers · asked by senorita_otono 2 in Mathematics

A woman at an airport is towing her 23.0 kg suitcase at constant speed by pulling on a strap at an angle of θ above the horizontal. She pulls on the strap with a 36.5 N force, and the friction force on the suitcase is 20.0 N.

(b) What angle does the strap make with the horizontal?

(c) What normal force does the ground exert on the suitcase?

2007-09-19 05:13:54 · 2 answers · asked by surfing86 2 in Physics

2007-09-19 05:13:47 · 19 answers · asked by RAY C 1 in Mathematics

A 1.00 kg object is observed to have an acceleration of = 19.0 m/s2 in a direction θ = 33.0° north of east. The force 2 acting on the object has a magnitude of 10.3 N and is directed north. Determine the magnitude and direction of the force 1 acting on the mass.

2007-09-19 05:12:49 · 1 answers · asked by surfing86 2 in Physics

Bromine has two naturally occurring isotopes ( Br-79 and Br-81) and has an atomic mass of 79.904 amu . The mass of Br-81 is 80.9163 amu, and its natural abundance is 49.31%. Calculate the mass of Br-79? how do you find the mass.

2007-09-19 05:12:34 · 1 answers · asked by Chuck 1 in Chemistry

2007-09-19 05:10:09 · 1 answers · asked by itqueen293 2 in Mathematics

This "basic" step in evolutionary theory seems to be taken as a given. But what was the mechanism that caused it? I've always found this irrational.

2007-09-19 05:03:22 · 9 answers · asked by Suzanne 5 in Zoology

I use tin plating with thickness 5.5 micron over steel, when it undergo soldering at 220 degree C, the plated surface form cluster causing rough surface. what thickness should i use or other plating materials to be recommended to overcome rough surface? i had tried silver and gold plating, its good but cost too high.

2007-09-19 05:02:55 · 3 answers · asked by Erica L 3 in Engineering

3x + 2y = 15
2x - 3y = 9

how do you solve this question using algebra simultaneous equations.

2007-09-19 05:02:15 · 4 answers · asked by Anonymous in Mathematics

i think that earth is a molecule, or an atom, a thing that makes up a cell, the universe makes up a part of a cell, a few universes added together makes up a 'cell.' or atom
this cell or atom makes up an object or tissue in an organ.
and that in side human cells are 'galaxies' and inside their cells are another life form.
or the earth is floating in dust in side an object made of particles of 'universes'
anyone agree only slightly??

2007-09-19 04:56:59 · 14 answers · asked by Anonymous in Astronomy & Space

For a>0 and b>0 with a not equal to b, show that the square root of (ab) < (a+b)/2

I feel like I should be solving this by contradiction, and I keep trying, but I haven't managed to come up with it yet. I can't get it to work for some reason.

2007-09-19 04:56:29 · 3 answers · asked by yogastar02 2 in Mathematics

Lets assume that planet Earth is the only massive body around here, and moves at speed 1km/s towards a huge field of almost motionless small rocks. The concenteration of rocks is 1 rock per 1,000,000 km³ (n = 1e-6/km³).

http://i16.tinypic.com/4vefxjr.jpg

What will be the rate of bombardment of the entire planet (rocks per second) when it enters the field?

2007-09-19 04:53:30 · 2 answers · asked by Alexander 6 in Physics

Oxidation: 2H(2)O(2) --- 2 O(2) + 4H(+) + 4e-
Reduction: Fe (3+) + e- ---- Fe (2+)

Combine the two half reactions to obtain a balanced overall redox reaction.

**(All () numbers or symbols are () to show they are sub numbers and symbols)

If anyone has any suggestions I would really appreciate it! Thank you

2007-09-19 04:52:07 · 1 answers · asked by Mary 1 in Chemistry

You toss a chocilate bar to your hiking companion located 8.6 m up a 39 degree slope.determine the initial velocity vector so that chocolate bar will reach your friend moving horizontal??

2007-09-19 04:49:05 · 5 answers · asked by M R 1 in Physics

A woman deposits $50,000 in a savings account with 4% continuously compounded interest. How many years must she wait until the balance has doubled?


Assume that the number of viruses present in a sample is modeled by the exponential function "f(t) = 10t," where t is the elapsed time in minutes. How would you apply logarithms to determine when the sample will grow to 5 billion viruses?



THANKS FOR THE HELP

2007-09-19 04:48:40 · 4 answers · asked by crackr 3 in Mathematics

Describe the means of how these seeds are dispersed.
-Tell how the seeds of this plant would be transported to a place away from the parent plant.


Here is where the seeds came from
- peach
-lemon
- weeds( “stickers” or “hitch-hiker” type seeds.)
-acorn
- apple

2007-09-19 04:46:37 · 2 answers · asked by ♥~Onyx~♥ 5 in Botany

it is the push or pull but when we apply force on aaa downward table why dont we see any efect of force?

2007-09-19 04:45:34 · 2 answers · asked by A`A A 1 in Physics

prove that a line tangent to the parabola x^2=4py at the point(a,b) crosses the y-axis at (0,-b)

2007-09-19 04:44:27 · 2 answers · asked by yassem1ne 2 in Mathematics

I was asked this years ago (by a Boy Scout, no less!) and was unable to provide an answer, specially since Scout came to be one of the most dependable launch vehicles ever. It was also known as LTV Scout and was employed in several variants, including (for the military, I believe), the so-called Blue Scout.

2007-09-19 04:41:57 · 1 answers · asked by alactasic 1 in Astronomy & Space

2007-09-19 04:37:54 · 3 answers · asked by Anonymous in Engineering

What is (a surd question) in the form a + b Root* something.

I vaguely recall a question being something like that. Please show working.

2007-09-19 04:37:34 · 2 answers · asked by hurrahx 2 in Mathematics

If yes, what is the maximum temperature the human body can be raised to?

2007-09-19 04:34:10 · 6 answers · asked by gumtrunk 2 in Biology

Hi, I'm a little stuck on this question.

I have the original graph y=x(6-x)

And I have another graph with points that go through (0.0), (1.5,4.5) and (3,0)

I think that it has been compressed by horizontally and vertically. And I believe the function of the is y=1/2f(2x). But I'm not sure. I'm wondering what the equation of this line would be. Any help would be appreciated. Thanks in advance.

2007-09-19 04:22:59 · 1 answers · asked by henry7836 2 in Mathematics

how do you rationalise each denominator in:

1
__
(square root) v3


+


1
___
v5



and then express it as a single fraction?


please explain each step carefully and thoroughly.

thanks!
best answer is for first answer which is correct

but if someone answers before you they might not get best answer because their answer might not be as good as yours.

best answer is waiting.

2007-09-19 04:20:57 · 4 answers · asked by Anonymous in Mathematics

I thought their behavior around the nest was strange, they were just sort of huddled around not appearing to be doing much of anything There were several dozen and since the nest was on my front porch, I had to get rid of it.

Now they (not the same ones, obviously) are huddled in a new spot a few feet away from the old nest, not building a new nest -- but they also don't appear to be leaving. There are about a dozen of them; I never see them flying around although they twitch at each other a lot.

What are they doing? (Besides plotting their revenge against me....)

2007-09-19 04:17:58 · 5 answers · asked by . 4 in Zoology

x=2
y=4

How do i do this and wat is the answer! we are doing coordinates and lines.

Thanx

2007-09-19 04:17:21 · 7 answers · asked by Matt 4 in Mathematics