For this question I answered part A. But I am lost on what I am suppose to do for question B.

Given d varies jointly as r and the square of s and inversely as t and d =8 when r=3, s=2, and t=6.

A. What is the constant of proportionality? Show your work.

8=k(3)(2)^2 / 6
K=4

B. Using your answer from part a, determine the equation of variation for d.

d=krs^2/t where k=4

d=4rs^2/t