Answer:

Explanation:
If r varies directly with the square of m and inversely as s,
then
where k is some constant
Given r = 12 when m = 6 and s = 4:
⇒
⇒

⇒ k =

Therefore, substituting the found value of k into the original equation:

Find r when m = 4 and s = 10:

⇒

⇒
