Science & Mathematics - 23 October 2007

I've been googling for hours yet again...! Thanks for any help!

ACROSS

3. The part of a building or other structure above the foundation (14 letters)
10. A group or set of four (6)
12. The layer or bed of earth under the topsoil (7)
15. A biologically ancestral form. Comes before the present day species (9)
17. Existing or ocurring before birth (8)
18. Normal firmness, tension, or functional readiness in body tissues or organs (8)
23. Of, relating to, or containing salt; salty (6)
24. Causing sepsis; causing something to rot (5)
29. Located behind a part or toward the rear of a structure (9)
30. Rootlike filaments seen in some nonplants such as certain fungi (7)
33. True to the life; exhibiting the appearance of life or freshness;animated; spirited; bright; strong (5)
41. Of or relating to a molecule that has three or more atoms as constituents (10)
42. The cell formed by the union of two gametes, such as sperm and eggs, resulting in a fertilized ovum (egg) (6)

2007-10-23 16:34:56 · 3 answers · asked by Anonymous in Biology

A 100.-mL sample of solution contains 10.0 mmol of Ca2+ ion. How many mmol of solid Na2SO4 must be added in order to cause precipitaton of 99.9% of the calcium as CaSO4? The Ksp of CaSO4 is 6.1 x 10^-5. Assume the volume remains constant.

Please help, I don't know the steps to do these kinds of problems.

2007-10-23 16:34:55 · 1 answers · asked by Anonymous in Chemistry

2007-10-23 16:29:19 · 13 answers · asked by sofnesh 1 in Astronomy & Space

2007-10-23 16:28:42 · 1 answers · asked by TAns 2 in Biology

I can't find any mention of them anywhere on the internet.

2007-10-23 16:26:45 · 3 answers · asked by Mary S 2 in Astronomy & Space

Because precession happens approximately 20000 years and given the fact that during our summers, we are farthest from the sun. Does this mean in 10000 years we will be closest to the sun during the summer and farthest during winter?

2007-10-23 16:26:08 · 2 answers · asked by Anonymous in Astronomy & Space

Suppose that 3 ≤ f’(x) ≤ 5 for all values of x. Show that 18 ≤ f(8) – f(2) ≤ 30.

2007-10-23 16:22:32 · 2 answers · asked by Britt R 1 in Mathematics

its a story problem. I got the correct answer (at least I think it's the correct answer) but I didn't use an algebraic formula. Can you explain how to do the problem in algebraic terms. THANKS:

Geri had an average of 80% on four tests. What score must she get on the next test to raise her average to 83%.

I know the problems not too hard, but whenever I have to think of a way to write it algebraically it always seems to take forever. UGH! maybe I'm just not very good at these things.

How would you do it algebraically?

2007-10-23 16:21:45 · 10 answers · asked by Anonymous in Mathematics

description of how these toxins work or what they do the unfortunate predator. urushiol, methylmercaptan,tetrodotoxin,gossypol,ricin,avidin, t-2toxin,amanitin,cyanogenic glycosides,stachbotrys. please help me

2007-10-23 16:21:31 · 1 answers · asked by giovanni z 1 in Biology

I Need help finding the critical points for 11+30x+18x^2+2x^3. how do i factor wit 4 sets of numbers?

2007-10-23 16:20:41 · 3 answers · asked by sleepingdogslay 1 in Mathematics

If v = t^2 + 4m/s what is the acceleration at times (acceleration not constant):
t=1s and t=4s

I've worked out that V=5 at 1s and V=20 at 4s using the initial formula...

And then supposedly meant to use this formula to find accelleration => a=dv/dt...

But if you know an easier way that would be even better

Thanks guys

2007-10-23 16:20:01 · 2 answers · asked by Anonymous in Physics

The two top-selling DVDs of 2003 grossed a combined total of $600.9 million. the top-selling DVD grossed $39.9 million more than the DVD ranked second. ow much did the top-selling DVD gross?

2007-10-23 16:19:07 · 3 answers · asked by ShaZ 1 in Mathematics

Organic solid such as naphthalene and 1, 4-dichlorobenzene are widely used as mothballs b/c they are toxic to insects ans sublime at a slow rate at atmospheric pressure. Other organic solids such as urea and lactic acid do not have any appreciable vapor pressure under ambient conditions. Explain this behavior in terms of the structure of the molecules.

2007-10-23 16:18:19 · 1 answers · asked by Anonymous in Chemistry

If a complex number z is represented by the point P as shown in the figure below and the circle is a unit circle, then which of the eight regions (R, S, T, U, V, W, X, Y) contains the reciprocal of z. Prove your answer.

2007-10-23 16:18:12 · 1 answers · asked by Keytosuccess 1 in Mathematics

Could someone explain the steps of how sound is made? Does vibration cause energy, or does energy create the vibration?

Thanks!

2007-10-23 16:17:21 · 6 answers · asked by Anonymous in Other - Science

the side have lengths a,b and, c. The ratio of b to a is 3:5, and the ratio of c to a is 7:5. Find the length of each side

I NEED HELP and like all the steps to figure this out plz!!

2007-10-23 16:17:12 · 3 answers · asked by TrackStar22 2 in Mathematics

could someone give me at least the steps or how to get the steps to doing this problem?

lim as x goes to infinity of the function

(ln((square root of x) +5)) / ln(x)

Note it is not the square root of the quantity (x+5); it is only the square root of x then the plus five is outside of the square root.

2007-10-23 16:16:39 · 3 answers · asked by Anonymous in Mathematics

why we can't say P= 0.000?

Thank you

2007-10-23 16:13:23 · 2 answers · asked by bluesky8 1 in Mathematics

I've tried it before and it never works.

2007-10-23 16:12:45 · 25 answers · asked by Arctic Wolf 3 in Parapsychology

2007-10-23 16:10:07 · 8 answers · asked by sportsfanatic1089 2 in Chemistry

2007-10-23 16:08:20 · 4 answers · asked by Anonymous in Chemistry

I understand that some landscapes require natural fires every few years to remain healthy. We stop fires from happening near homes, and this is not good for the forest-- that is why we have prescribed burns. But, how would a fire "naturally" start every few years if left untouched by humans? Is lightning the ONLY reason?

2007-10-23 16:03:24 · 18 answers · asked by Xiao-wen 2 in Earth Sciences & Geology

tan 2x + 2sin x = 0

2007-10-23 16:01:34 · 1 answers · asked by GetSmart =) 2 in Mathematics

2007-10-23 16:00:52 · 10 answers · asked by Anonymous in Weather

2007-10-23 15:59:54 · 3 answers · asked by valerie_dvs 1 in Biology

Show that the functions in this interval have exactly one zero in the given interval,

~ This is inside the rolle's theorem, Mean Value Theorem section in calculus.

F(x)= x + (sin(x/3))^2 -8 on the interval (-infinity, infinity)

2007-10-23 15:59:38 · 1 answers · asked by whatsntomake 1 in Mathematics

2007-10-23 15:57:14 · 6 answers · asked by Trickster 1 in Mathematics

I am sorry, now, corrected the question, I was not feeling well, last night. I sincerely regret, please excuse me.

2007-10-23 15:55:49 · 2 answers · asked by indrajeet d 5 in Other - Science

2007-10-23 15:54:40 · 4 answers · asked by Shakera L 1 in Biology

Factor Completely
x^2 – 5x – 84

2007-10-23 15:53:45 · 5 answers · asked by sumguy 1 in Mathematics