Answer:
56cm²
Explanation:
the amount of material he needs would be the total surface area of the box. surface area can be calculated by finding the sum of surface area of all the sides of the box. since the opposite sides are equal, we can find the surface area of 3 different sides and then multiply it by 2.
(4 + 4) + (4 + 6) + (6 + 4) × 2
= 8 + 10 + 10 × 2
= 28 × 2
= 56cm²
i hope this helps! :D