Answer:
142 cm squared
Step-by-step explanation:
the formula used was 2(lw + wh +lh)
where l is length
w is width
and h is height
142
5 x 3 = 15 Times by 2 = 30
7 x 5 = 35 Times by 2 = 70
7 x 3 = 21 Times by 2 = 42
