Answer:
A. 140 cm
B. 3780 cm
Explanation:
The volume formula for a rectangular prism is lwh, and 7 times 4 times 5 equals 140.
If you triple all those amounts, then you get 21 (7 times 3), 12 (4 times 3), and 15 (5 times 3), and when you multiply those you get 3780.
I hope this helps :)