Science & Mathematics - 30 August 2007

I don't know..please help me.

2007-08-30 16:08:24 · 1 answers · asked by shadowpal2 2 in Chemistry

...has at least one solution.
If false, please explain.
Thank you.

2007-08-30 16:04:52 · 4 answers · asked by Red 2 in Mathematics

t=0.2s+10 and 4s+5t=35

its not a graph, you have to solve using substitution..

2007-08-30 16:04:50 · 6 answers · asked by Anonymous in Mathematics

Viruses
b. Archaea
c. Fungi
d. Monera
e. Bacteria

2007-08-30 16:03:31 · 6 answers · asked by ursportsguy 1 in Biology

What is -4.8? [List which of the following]
Rational
Irrational
Integer
Whole Number
Natural

please only answer this if you KNOW the answer
Thank you!

2007-08-30 16:02:43 · 6 answers · asked by Tallito 1 in Mathematics

2007-08-30 16:00:14 · 10 answers · asked by kingdk 1 in Weather

2007-08-30 15:58:25 · 5 answers · asked by Viktor 1 in Biology

does anyone know a fun easy science project?

2007-08-30 15:58:07 · 5 answers · asked by Joss 1 in Chemistry

9:
(x3 + 4x2 - 2x + 5) - (3x3 - 3x2 + x - 2)
-2x3 + x2 - x + 3
-2x2 + 7x - 3x + 3
-2x3 + 7x2 - 3x + 7

10: Factor the following polynomials.
3x2 + 7x + 2
(3x + 3)(x + 2)
(3x + 1)(x + 2)
(x + 1)(x + 2)

11:
x4 + x2 - 6
(x2 - 2)(x2 + 3)
(x2 + 2)(x2 + 3)
(x2 - 2)(x2 + 2)

12:
64x2 - 9
(8x + 3)(x + 3)
(8x – 3)(8x + 3)
(4x – 3)(2x - 3)

13:
x3 - 1
(x – 1)(x2 + x + 1)
(x – 1)(x2 + 1)
(x – 1)(x2 + x - 1 )

14:
54x7 + 16x
x(3x2 + 2)(9x4 - 6x2 + 3)
2x(3x2 + 2)(9x4 - 6x2 + 4)
2x(3x2 + 1)(9x4 - 6x2 + 3)

15: Solve the following equations.
12m2 + 7m = -1
0, -5
-3/4, 3/2
-1/3, -1/4

16:
8(c3 - c) = c (6c + 1)
2, -5
0, -3/4, 3/2
3/4, 3/2

17: Simplify the following rational expressions:

(x2 - 1) · (x2 + 5x + 6) · (x2 - x - 20)
(x2 - 3x - 10) (x2 - 3x – 4) (x2 + 2x – 3)
(x + 4) / (x - 4)
(x + 4)(x - 4)
(x + 4) / (x + 4)

18:

(6x – 9) ÷ (6 – 13x + 6x2)
(5x +1) (15x2 - 7x – 2)
2
3
2x + 1
19:

(y – x) + (x + y)
(x2y) (xy2)
x2 + xy2
(2x2 + y2) / (x2y + 1)
( y2 + x2) / (x2y2)

2007-08-30 15:57:28 · 2 answers · asked by Anonymous in Mathematics

when shooting and arrow than the string in bow B. Which bow gives its arrow a greater acceleration? Or, do neither give their arrow acceleration?

2007-08-30 15:53:48 · 3 answers · asked by Diff 1 in Physics

find the average speed for the given distance and time. show the unit analysis to check units,
problem:
in 5 seconds, an athlete runs 40 feet.



please and thank you....

2007-08-30 15:51:45 · 8 answers · asked by Anonymous in Mathematics

please see the link for question

http://answerboard.cramster.com/physics-topic-5-94227-0.aspx

2007-08-30 15:49:54 · 1 answers · asked by wake up 1 in Physics

For a positive integer n, let Pn denote the product of the digits of n, and Sn denote the sum of the digits of n. The number of integers between 10 and 1000 for which Pn + Sn = n is

(a)81

(b)16

(c)18

(d)9

books soln :
--------------------
Let the number be xy. Then xy + x + y = 10x + y -> xy = 9x -> y = 9. The values that will satisfy the given conditions are: 19, 29, 39, 49, 59, 69, 79, 89, 99. Hence there are 9 such values.


the soln looks fine.

But see, book has taken only 2 digit number .

what about 3 and 4 digit and more digit numbers ?
it seems to me the soln given is not fair.

I need to understand why the more digit numbers are ignored.

2007-08-30 15:46:09 · 1 answers · asked by calculus 1 in Mathematics

I have V takeoff=134 m/s, t takeoff=26.83,
A plane accelerates from rest at a constant rate of 5.00 meters/ seconds squared along a runway that is 1800M long. Assume that the plane reaches the required takeoff velocity at the end of the runway.

2007-08-30 15:45:35 · 3 answers · asked by osu9295 1 in Physics

its for an anatomy and physiology assignment and i dont want to put that down if im wrong :)

2007-08-30 15:43:01 · 2 answers · asked by Terra 6 in Medicine

A study of Brand D washing machines that failed within three years (warranty period) was 28.7%. Of those that failed, 85.02% lasted over two years. What is the probability that a washer, which lasts at least two years, will still fail before the end of the warranty period?

2007-08-30 15:42:35 · 1 answers · asked by pumpkin 2 in Mathematics

Given stock solutions of glucose (2M), glycine (200mM), and NaCl (500mM), how much of each solution do you need to prepare 500 mL of a reagent that contains 0.05 M glucose, 10 mM glycine and 10 mM NaCl?


Do I just use the equation of M1V1=M2V2?

(2M)(?)=(0.05M)(0.5L) ?=0.0125L of glucose

(0.2M)(?)=(0.01M)(0.5L) ?=0.025L of glycine

2007-08-30 15:42:27 · 1 answers · asked by Anonymous in Chemistry

my son would like to know if someone out there knows what it is that makes them pop and if it could be made at home. i'm guessing it's some kind of cardon dioxide thing going on but, i really have no idea. thanks for your help.

2007-08-30 15:42:01 · 2 answers · asked by racer 51 7 in Chemistry

I hear that if you can keep your reflection from blocking you from entering the other realm, you are in for a treat.

Wow, has anyone ever been there? I spend hours infron of my mirror, but everywhere i put my hand, my reflection puts her hand. Frustrating but I think I am getting closer.

2007-08-30 15:40:24 · 18 answers · asked by Royal 4 in Astronomy & Space

I need to know how to find the y-intercept when given two points. (4,3) (-4,-4)

I got that it was -1/2 but my sister got -1. Which one is correct, or are we both wrong?

2007-08-30 15:40:16 · 5 answers · asked by Sarah 4 in Mathematics

dont just guess to get the points.. back up your answer or give a link

2007-08-30 15:36:04 · 11 answers · asked by Terra 6 in Medicine

I'm currently a 4th year med student and have high chances of starting my internship year around July 2008. I haven't chosen the city I'll do it in, but I'm currently between 1 private hospital in Mexico City very close to where I live and two public hospitals in Toluca.

I'm mainly curious about what other people's experiences have been regarding their internship year. They say that the internship can be the best days of your life or the worst and can mean quitting the career before finishing it to pursue something completely different.

Several pals have started or are halfway through it but they are so busy I rarely see them. I'd rather hear it from people that have finished it.

Note that in Mexico I'll still have to do a 6th year in Social Service but internships here shouldn't be that different from the US.

2007-08-30 15:33:40 · 5 answers · asked by Gata de Barrio 6 in Medicine

Could someone help me with this. I have tried to get the correct answer and it is still wrong unless my paper has a typo. My answer is 381.86 cubic meters.
Find the volume of a sphere that has a diameter of 9 meters.
Please work out so I can understand......

2007-08-30 15:29:48 · 6 answers · asked by Tim M 1 in Mathematics

I'm kinda stuck on how to do these if someone could work it a few out for me i'd appreciate it I don't remember the processes of this crap

7(a+1)-3a=5+4(2a-1)


0.5(2x+3/4)-1/3 (.1+x)=1

solve for variable 'v' ; h=vt-5t^2

'b2'; A= 1/2h(b1+b2)

2007-08-30 15:28:24 · 3 answers · asked by Anonymous in Mathematics

Floor plans for a building have the four corners of a room located at the points (2, 3), (11, 6), (-3, 18), and (8, 21). Determine whether the side through thepoints (2, 3) and (11, 6) is parallel to the side through the points (-3, 18) and (8, 21).determine whether the side through the points (2, 3) and (11, 6) is perpendicular to the side through the points
(2, 3) and -3, 18)

2007-08-30 15:26:26 · 1 answers · asked by Anonymous in Engineering

I'm stuck, I'm in calculus but can't remember how to factor this one out to find the zeros.

2007-08-30 15:26:00 · 2 answers · asked by Anonymous in Mathematics

b) How many molecules of a gas will be produced?

Please show me how to get to the solution also. Thanks!

2007-08-30 15:24:10 · 4 answers · asked by hotlilmamax2 1 in Chemistry

If a person produces 175 widgets each day, how many widgets do I need to quality check each month to ensure they are creating a quality widget?

2007-08-30 15:23:37 · 4 answers · asked by Chris 2 in Mathematics

2007-08-30 15:23:29 · 5 answers · asked by Anonymous in Astronomy & Space

Technology. Driving down a mountain, Tom finds that he has descended 1800 ft
in elevation by the time he is 3.25 mi horizontally away from the top of the
mountain. Find the slope of his descent to the nearest hundredth.

2007-08-30 15:19:50 · 2 answers · asked by Anonymous in Mathematics