The answer is d. 384 m3.
The volume (V) of the box is:
V = l × w × h
l - the length of the box
w - the width of the box
h - the height of the box
If V1 = 48 m³ = l × w × h and all its dimensions are doubled to create box B, then:
V2 = 2l × 2w × 2h = 2 × 2 × 2 × l × w × h = 8 x l × w × h
We know that l × w × h is 48 m³, so:
V2 = 8 x l × w × h = 8 × 48 = 384 m³
