Science & Mathematics - 11 September 2007

P<->Q = (P->Q) ^ (Q->P)

2007-09-11 08:51:34 · 1 answers · asked by Anonymous in Mathematics

suggest the likely ions that would be formed by a calcium atom and how?

2007-09-11 08:50:23 · 2 answers · asked by monika 2 in Chemistry

2007-09-11 08:50:05 · 16 answers · asked by rydar 1 in Geography

2007-09-11 08:49:28 · 5 answers · asked by Felipe Cruz 1 in Mathematics

is fridge temperture degrees 3 colder than 4

2007-09-11 08:47:03 · 4 answers · asked by Tracey D 1 in Weather

2007-09-11 08:43:54 · 3 answers · asked by Anonymous in Earth Sciences & Geology

2007-09-11 08:41:36 · 5 answers · asked by Anonymous in Earth Sciences & Geology

Is there a formula (preferably a calculator on the web) that can estimate the power lost over long extension cord runs? On the Sears web site they sell a 16/3 cord 100 feet long. It says 13 amps up to 50 feet and 10 amps up to 100 feet. So if I need to connect 4 of these to go 400 feet I want to know about how many amps I would really have available at the end. Also, I would like to do other calculations for going even longer distances up to 900 feet.

2007-09-11 08:38:42 · 5 answers · asked by Darren 2 in Engineering

2007-09-11 08:38:14 · 12 answers · asked by Stan S 1 in Astronomy & Space

books about psychic phenomena, spirituality, law of attraction, anything "paranormal", dreams whatever

2007-09-11 08:37:39 · 10 answers · asked by Anonymous in Paranormal Phenomena

2007-09-11 08:37:10 · 5 answers · asked by Stan S 1 in Astronomy & Space

the triangle is a right angle trianglle. The bottom line is 42' , the side line is 31' and the slanted line is x. How do i figure it out?

2007-09-11 08:35:43 · 6 answers · asked by tytyylleerr 1 in Mathematics

What was he famous for?

2007-09-11 08:34:35 · 9 answers · asked by Sophiee 4 in Other - Science

Does anyone know a country starting with w and x?

2007-09-11 08:34:16 · 3 answers · asked by lozcally 1 in Geography

How does animals teeth look like if the animals could eat both plants and animals? Please tell me ? I kn that animals that eat plants have flat teeth and animals eat meat have sharp teeth!

2007-09-11 08:33:49 · 4 answers · asked by (: 3 in Zoology

{-1/4,2/9,-3/16,4/25,...}

thanks alot for your help.thankssssss

2007-09-11 08:33:44 · 1 answers · asked by joy 1 in Mathematics

2007-09-11 08:33:23 · 7 answers · asked by kenzie b 1 in Weather

2007-09-11 08:28:09 · 2 answers · asked by ccutestuff2001 2 in Chemistry

2007-09-11 08:27:16 · 7 answers · asked by Rohan S 1 in Astronomy & Space

Though what do you think??? L:l and why ?

2007-09-11 08:25:45 · 16 answers · asked by apples and pears 4 in Astronomy & Space

Vincente and Ricarda Perez have invested $27,000 in bonds paying 7%. How much additional money should they invest in a certificate of dposit paying 4% simple interest so that the total return on the two investments will be 6%?

2007-09-11 08:24:49 · 3 answers · asked by Jenn 2 in Mathematics

What do the stars mean in here? How do I do this?

2007-09-11 08:23:22 · 4 answers · asked by Manda J 4 in Astronomy & Space

Can someone plz help with this prob. thanksssss
a sub n= (-1)^(n-1)n/ n^(2) +1

2007-09-11 08:23:17 · 1 answers · asked by joy 1 in Mathematics

a) Factor one expression by grouping terms

x^5+x^4+x+1

b) Factor one expression completely

(a^2-1) b^2-4 (a^2-1)

c) Factor one expression completely. Begin by factoring out the lowest power of each common factor

x^-1/2 (x+1)^1/2 + x^1/2 (x+1)^-1/2

2007-09-11 08:23:08 · 2 answers · asked by alexo 4 in Mathematics

what kind of number?

2007-09-11 08:15:23 · 10 answers · asked by Anonymous in Mathematics

A piece of Nichrome wire has a radius of 6.5 x 10^-4 m. It is used in a laboratory to make a heater that dissipates 6.00 x 10^2 W of power when connected to a voltage source of 120 V. Ignoring the effect of temperature on resistance, estimate the necessary length of wire.

2007-09-11 08:14:52 · 2 answers · asked by Anonymous in Engineering

1)dy/dx=(1-y)cosx , y(pi)=2

and

2)dy/dx+ycotx=cosx

I've tried so much with these, but they are getting really messy, and I am getting really strange answers.

2007-09-11 08:13:16 · 2 answers · asked by dtsairman 3 in Mathematics

Parallel wiring question....

What resistance must be placed in parallel with a 155 ohm resistor to make the equivalent resistance 112 ohms?

Any help is appreciated!!

2007-09-11 08:12:45 · 5 answers · asked by Anonymous in Engineering

I'm not exactly sure how to do this particular problem I don't know why kind of graph I'm supposed to use. Thanks for any help!

Question:
Listed below are the survival times in days of 72 guinea pigs after they were injected with infectious bacteria in a medical experiment. Survival times, whether of machines under stress or cancer patients after treatment, usually have distributions that are skewed to the right.

Data:
43, 45, 53, 56, 56, 57, 58, 66, 67, 73, 74, 79, 80, 80, 81, 81, 81, 82, 83, 84, 88, 89, 91, 91, 92, 92, 97, 99, 99, 100, 100, 101, 102, 102, 102, 103, 104, 107, 108, 109, 113, 114, 118, 121, 123, 126, 128, 137, 138, 139, 144, 145, 147, 156, 162, 174 178, 179, 184, 191, 198, 211, 214, 243, 249, 329, 380, 403, 511, 522, 598

(a) Graph the distribution and describe its main features. Does it show the expected right shew?
(b) Which numerical summary would you choose for these data? Calculate your chosen summary. How does it reflect the skewness of the distribution

2007-09-11 08:10:53 · 3 answers · asked by Anonymous in Mathematics

Two resistors, 35.0 ohms and 64.0 ohms, are connected in parallel. The current through the 64.0 ohm resistor is 3.40 A.

(a) Determine the current in the other resistor.
(b) What is the total power consumed by the two resistors?

Any help is appreciated, I cannot figure out how to solve this without knowing the voltage across the power source????

2007-09-11 08:10:42 · 7 answers · asked by Anonymous in Engineering