Answer:
28.8 and 180
Explanation:
you just times B by 2/5 to get C and divide it by 2/5 to get A
C = (72)(2/5) = 28.8 km³
A = (72)/(2/5) = 180 km³
We know the answers make sense because A shrinks to get B and B shrinks to get C, and our answers match that.