Science & Mathematics - 28 October 2007

1.) Does this limit =0? or am I wrong?
Lim sin(pi/x)
x>0
2.) Does this limit exist?
Lim xsin(1/x)
3.) Is there a number such that the limit Lim as x tends to 0 of 2x^2-3ax +x - a - 1/ x^2 - 2x - 3

2007-10-28 15:23:02 · 1 answers · asked by Jessica 4 in Mathematics

A container of volume V = 1.9 litres has a mass of 51.028 g when evacuated. When the container is filled with air pressure p = 3.4 atm at a temperature T = 30oC, what is the mass of the system? Treat air as an ideal gas with molar mass M = 28.25 g/mol.
Express the result in the unit [g] and to three significant figures. If you must use scientific notation, please enter as follows: e.g. 0.000123 = 1.23E-4. Please show all calculation steps so that I understand how the answer is determined

2007-10-28 15:22:57 · 2 answers · asked by Penny M 1 in Physics

a. 145.3 yd^2
b. 42.7 yd^2
c. 36.3 yd^2
d. 21.4 yd^2


thank u!

2007-10-28 15:22:45 · 9 answers · asked by Anonymous in Mathematics

2007-10-28 15:22:34 · 6 answers · asked by Travis G 1 in Mathematics

2007-10-28 15:21:18 · 7 answers · asked by martinlh 4 in Astronomy & Space

2007-10-28 15:19:13 · 1 answers · asked by Maryajne B 1 in Astronomy & Space

Could it actually change

2007-10-28 15:16:04 · 4 answers · asked by rst41 2 in Physics

a.rain
b.river
c.runoff
d.ground water

2007-10-28 15:14:25 · 5 answers · asked by Anonymous in Earth Sciences & Geology

2007-10-28 15:12:43 · 4 answers · asked by girl123 1 in Geography

I don't think so! I think it is shining the brightest it has been in years!

What a special moon!

A beautiful Moon!

A caring Moon!

A sensitive Moon!

I think it is time to worship our Moon :)

What do you think?

2007-10-28 15:12:28 · 15 answers · asked by Icy Gazpacho 6 in Astronomy & Space

f (x) = 3 sqrt (8x+9)


f(101)

2007-10-28 15:09:49 · 4 answers · asked by ry ry 3 in Mathematics

Find the minimum value of

216((xsinx)^2)/5 + 36xsinx + 30 + 25/(xsinx) + 125/(6(xsinx)^2)

for 0 < x < pi.

2007-10-28 15:08:08 · 4 answers · asked by absird 5 in Mathematics

the universe?

2007-10-28 15:07:36 · 16 answers · asked by sadie161994 1 in Astronomy & Space

The sodium-potassium pump is called an electrogenic pump because it:
a. pumps equal quantities of Na and K across the membrane
b. pumps hydrogen ions out of the cell
c. contributes to the membrane potential
d. ionizes sodium and potassium atoms
e. is used to drive the transport of the other molecules against a concentration gradient

Thank you for your time.

2007-10-28 15:07:15 · 0 answers · asked by . 6 in Biology

Is the cathode the steel case, or is it the Oxide (e.g. Mercury Oxide)?

2007-10-28 15:06:47 · 2 answers · asked by dani 1 in Chemistry

hi, i need some help on demonstrating the electrical activity of a contracting muscles and how it spread to the skin surface. please list a link web sites that can help me understand this topic........

2007-10-28 15:04:41 · 1 answers · asked by Young_city 1 in Biology

If you drew a random line (vector) from earth, would the vector almost certainly hit a star?

Or would the vector most likely continue to the edge of the known universe (assume "Big Bang") without touching a star?

2007-10-28 15:02:34 · 11 answers · asked by Anonymous in Astronomy & Space

Sodium ions (Na+) moave at 0.794 m/s through a bloodstream in the arm ofa person standing near a large magnet. The magnetic force has a strength of 0.26T and makes an angle of 69 degrees with the motion of the sodium ions. The arm contains 61.3 cm3 of blood (within the magnetic field) with 1.41 x 10^20 Na+ / cm3. If no other ions are present in the arm, what would be the magnetic force on the arm? Answer in units of N.

2007-10-28 15:01:48 · 1 answers · asked by Anonymous in Physics

2007-10-28 15:00:16 · 3 answers · asked by angel 2 in Mathematics

2007-10-28 14:59:40 · 7 answers · asked by Anonymous in Medicine

Anyone?

2007-10-28 14:58:07 · 3 answers · asked by Intuition 3 in Biology

im not really good with math :(

2007-10-28 14:53:01 · 9 answers · asked by DaNee' 2 in Mathematics

i have a huge exam tomorrow. i get everything except how to subtract negative numbers! whats an easy way or trick to remember how to do them!

2007-10-28 14:52:46 · 14 answers · asked by coloradogirl21 3 in Mathematics

(x to the 5/3 power) to the 6 power

2007-10-28 14:51:18 · 6 answers · asked by ry ry 3 in Mathematics

Describe the location and development of meristematic regions in an herbaceous and a woody plant.

I appreciate all the help i can get. Thanks in advance.

2007-10-28 14:49:11 · 1 answers · asked by Exodus 2 in Botany

In his explanation of the threshold frequency in the photoelectric effect, Einstein reasoned that the absorbed photon must have the minimum energy required to dislodge an electron from the metal surface. This energy is called the work function () of that metal. What is the longest wavelength of radiation (in nm) that could cause the photoelectric effect in each of the following metals?

(a) Tantalum, = 6.41 10-19 J

(b) Silver, = 7.59 10-19 J

(c) Tungsten, = 7.16 10-19 J

2007-10-28 14:48:35 · 1 answers · asked by Anonymous in Chemistry

why is it that when an enzyme is saturated,the only way to increase the productivtiy of a reaction is to add more enzyme?what can't enzyme do to a reaction?

2007-10-28 14:47:51 · 2 answers · asked by Anonymous in Biology

These are the only 4 questions I have left to answer out of 53... Please help..

1. The diameters of pencils produced by a certain machine are normally distributed with a mean of 0.30" and a sd of 0.01". In a random sample of 7 gross, approximately how many pencils would you expect to have a diameter less than 0.293"? A gross is a dozen dozen.Round your answer to the nearest whole number.

2. A certain grade egg must weigh at least 2 oz. If the weights of eggs are normally distributed with a mean of 1.5 oz and s.d. = 0.4 oz, approximately how many eggs in a random sample of 59 dozen would you expect to weigh more than 2 oz?

3. The amount of rainfall in January in a certain city is normally distributed with a mean of 3 inches and a standard deviation of 0.5 inches. Find the value of the quartile Q1.
a.3.3
b.2.7
c.2.8
d.0.8
4. Scores on a test have a mean of 89.1 and D2 is 75. The scores have a distribution that is approximately normal. Find the standard deviation.

2007-10-28 14:46:26 · 1 answers · asked by Anonymous in Mathematics

This is what I have so far, from the last question:::

84/2= 42
100 000/2= 50000

Then I divided each by 500, since 100 000/500 is 100. Then 42/500 is 0.084.

Is this the right answer? A simple yes, if it's right.

2007-10-28 14:42:39 · 2 answers · asked by Barbiex) 1 in Mathematics

Covalent bonds in a molecule absorb radiation in the IR range and vibrate at characteristic frequencies.

(a) The C-O bond in an organic compound absorbs radiation of wavelength 9.7 µm. What frequency (in s-1) corresponds to that wavelength?

(b) The H-Cl bond has a frequency of vibration of 8.634 1013 Hz. What wavelength (in µm) corresponds to that frequency?

2007-10-28 14:42:12 · 1 answers · asked by Anonymous in Chemistry