1,200 because 4x 3 is 12 and 40 x 30=1,200
The question only supplied us with the mass of the new baby which is:

This mass is too bizzarre & unrealistic for
Rectangle on the left = 3 × 4 = 12
Rectangle in the middle = 3 × 2 = 6
Rectangle on the right = 4 × 3 = 12
Add:
12 + 6 + 12 = 30
Answer = 30
Hope this helped☺☺
Ill answer it for you 150 cubic meters