Science & Mathematics - 30 October 2007

A Receptacle is in the shape of an inverted square pyramid 10cm in height and with a 6cm x 6cm square base. The volume of such pyramid is given by 1/3(area of the base)(height).
Suppose that the receptacle is being filled with water at the rate of .2 cubic centimeters per second. How fast is the water rising when it is 2cm deep?

Any help at all is greatly appreciated!!

2007-10-30 11:49:44 · 1 answers · asked by nicholas_obrien 1 in Mathematics

the questions are
1) Which number has all the following characteristics?
Its is prime
it is greater than 90
it is less than 100
it is not a multiple of 3

2) find x if x is prime and 23
3)The area of a rectangle is 36. What could be the dimensions of the rectangle if the lenght and width are whole numbers and neither is a prime number?

4)Find the common multiples of 8 and 20 that are less than 300

5)There is a prime number between 11 and 46 about which a teacher will answer three "yes" and "no" questions from her class. After answering the question, the first student to determine the correct number will get extra credit.
The students asked: 1. is it 5 or 6 more than a perfect square?
2) it is three more than a multiple of 7?
3)is the sum of its digits odd?
The answer were yes, yes, and no, respedtively. What is the number?

2007-10-30 11:49:27 · 8 answers · asked by babygirl 1 in Mathematics

How come an observer (of Polaris) in Southern Hemisphere will not be able to see the Polaris?


>>>>Help me plox

2007-10-30 11:48:51 · 4 answers · asked by XextrimityX 1 in Astronomy & Space

2007-10-30 11:48:50 · 3 answers · asked by Alexander 6 in Mathematics

Please someone help me.

I've been seeing people say (CH3COO)2 is Acetate but the formula of Acetate that I have is C2H3O2.

Is there something that I'm missing?

2007-10-30 11:48:17 · 5 answers · asked by shadow_zeke_raven 2 in Chemistry

2007-10-30 11:45:22 · 2 answers · asked by Jem 2 in Earth Sciences & Geology

know the question may seem a little complicated when first read, but I'll explain further. The objective is to write a function based on given information.

For f(x) for example...

If I'm given the type of equation (quadratic, cubic, quartic, etc), the leading coefficient, the constant, and the results of the evaluation of the expression for two x values (for example f(1)=a number, f(2)=another number)

And told to write a function that conforms to those requirements...how would I do this?

I think it involves systems of equations...but I'm not sure about that.

---

For further clarification, here's an example of what I mean.

f is a quadratic function
Leading Coefficient = 20
Constant = 20
f(1) = 20
f(2) = 200

Write an equation that conforms

---

Keep in mind that that scenario is a strict example; you don't need to solve it (it probably wouldn't work anyway haha). I just want to know how I would go about approaching a problem like this.

Sorry for the lengthy question heh

2007-10-30 11:45:21 · 2 answers · asked by Ryan 2 in Mathematics

I just looked up and saw a red light blinking slowly, and it hardly moved, but it was moving... lol... idk

2007-10-30 11:44:12 · 11 answers · asked by Anonymous in Astronomy & Space

what are the 8 major land regions of China?? pleease help!

2007-10-30 11:43:40 · 1 answers · asked by illypie 2 in Earth Sciences & Geology

thanks

2007-10-30 11:42:42 · 4 answers · asked by rockin.roxy:) 2 in Weather

What will happen to the convection currents in the mantle if Earth’s interior eventually cools down???

2007-10-30 11:41:33 · 2 answers · asked by Smile 2 in Earth Sciences & Geology

I am supposed to list three 3 real life levers except a seesaw and a wheelbarrow. It can be any class. URGENT!

2007-10-30 11:41:18 · 3 answers · asked by Dorinda 2 in Other - Science

THIS IS THE QUADRATIC FORMULA:
http://media.nasaexplores.com/lessons/01-003/images/quadform.gif

and this is formula for the sum of the roots: (-b/a) and the formula for the product of the roots is: (c/a)

How do I derive thee formulas for sum and product from the quadratic formula?

THANKS!

2007-10-30 11:39:50 · 3 answers · asked by Anonymous in Mathematics

the total amount of interest on a loan of $6,000 for 150 days is $210.50. Round the answer to the nearest hundredth.
a)2.34%
b)8.42%
c)8.53%
d)11.88%

2007-10-30 11:38:53 · 1 answers · asked by Kary M 1 in Mathematics

how far away will be the ball after 1 hour?

Orbital period is 2 hours.
'Sideways' means the ball is thrown in direction perpendicualar to obital plane.

2007-10-30 11:37:16 · 1 answers · asked by Alexander 6 in Physics

Lead (II) nitrate is a poisonous substance which has been used in the manufacture of special explosives and as a sensitizer in photography. Calculate the mass of lead in 139 g of Pb(NO3)2.

2007-10-30 11:37:05 · 1 answers · asked by April 1 in Chemistry

use the digits from 0 to 9 twice to fill in the 20 spaces in this multiplication problem.

_ _ _
x _ _ _
__________
_ _ _
_ _ _
_ _ _
__________
_ _ _ _ _

2007-10-30 11:36:41 · 2 answers · asked by Anonymous in Mathematics

2007-10-30 11:36:29 · 12 answers · asked by buzz5150 1 in Geography

How many grams of SF6 should be added to a sample of 486 g SF6 to obtain 5 moles of the compound?
244 g
730 g
114 g
33 g
none of the above, as 486 g represents more than 5 moles


What I understand is 5 Mol of SF6 x (146.07 g SF6/ 1 mol SF6 ) = 730.2 g SF6

Now do you divide that? and get

244.2g

or is the answer 730.2g?

2007-10-30 11:35:36 · 2 answers · asked by April 1 in Chemistry

A. 3, -4
B. -15, 3
C. 3, -5/3
D. -5/3, -4
E. -5, -3

2007-10-30 11:34:36 · 4 answers · asked by Anonymous in Mathematics

2007-10-30 11:33:36 · 9 answers · asked by Darryl Turner 1 in Mathematics

I have an object. I know the equation is a= Dv/Dt. My times are 2.8s and 4.0s. My velocities are 1.43 and 1.45. 10 points for giving the most thorough answer.

Also, show me how you did it please.

2007-10-30 11:33:27 · 1 answers · asked by Anonymous in Physics

The length of a table is measured to the nearest 1 cm and the value is found to be 100 cm. The clearest way to express this result is
100 cm
1 m
1.00 × 102 cm
1 × 102 cm
none of the above

I thought it could be either C or none of the above.. and I'm not sure I know 100. and 1.00 have the wrong sig figs..

2007-10-30 11:33:22 · 1 answers · asked by April 1 in Chemistry

I have an object. I know the equation is a= Dv/Dt. My times are 2.8s and 4.0s. My velocities are 1.43 and 1.45. 10 points for giving the most thorough answer.

Also, show me how you did it please.

2007-10-30 11:33:15 · 3 answers · asked by Anonymous in Engineering

Dispite this, collisions between the two are not possible. What are some possible reasons for this?

2007-10-30 11:30:07 · 4 answers · asked by Anonymous in Astronomy & Space

{Ar}...?

4s2 8p6?

2007-10-30 11:29:00 · 3 answers · asked by hgsaddgh 4 in Chemistry

How was the element nitrogen named?
What is its natural state?
What is the melting point?
What is its boiling point?
What group does it belong to in the periodic table?(such as noble gases or metal etc)
What are some of its characteristics? if its dangerous or explosive etc
And if you can please provide a link for a nitrogen electron cloud model picture. Thank you in advance

2007-10-30 11:27:40 · 2 answers · asked by legenddael 2 in Chemistry

2007-10-30 11:26:50 · 6 answers · asked by Anonymous in Geography

1.) 6x^2 - 13x - 5

(3x + 1)(2x - 5)

2.) 2x^2 + 15x + 7

(2x + 14)(2x - 1)

Can someone help me understand why these are diferent? why on the second one must i add the two "product" and "sum" to equal the middle

while the other one (1) only equals to "-5"

thanks

2007-10-30 11:26:26 · 1 answers · asked by Anonymous in Mathematics

g = 10 m/s/s
ignore air resistance

2007-10-30 11:25:37 · 10 answers · asked by Alexander 6 in Physics