Answer:
it's a very easy one and it's answer is 1728
Answer:
The answer is 
Step-by-step explanation:
Assuming the snowball is a perfect sphere, then if A denotes the surface area and D the diameter then:

Differentiating wrt r we have:

We are told that
and we want to find 
By the chain rule we have:

∴
∴
When D=10 then

The sign (-) shows that the D is decreasing.
Answer:
663
Step-by-step explanation:
the total number of students can be determined using this equation :
(total ratio of Chinese and Indian students / total ratio of students) x n = 468
total ratio of Chinese and Indian students = 4 + 8 = 12
total ratio of students 4 + 8 + 5 = 17
N = TOTAL NUMBER OF STUDENTS
12/17) x n = 468
multiply both sides of the equation by 17/12
n = 663