9514 1404 393
Answer:
1. no problem is stated
2. cube: V = s³; A = 6s². prism: V = lwh; A = 2(lw +h(l+w))
3. 400 cm²
Explanation:
1, 2. Answers shown above. The formulas are from your list of formulas.
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3. Cube surface area is ...
A = 6(20 cm)² = 2400 cm²
Prism surface area is ...
A = 2((40 cm)(20 cm) +(10 cm)(40 cm +20 cm))
A = 2(800 cm² +10(60) cm²) = 2(1400 cm²) = 2800 cm²
The difference in areas is ...
2800 cm² -2400 cm² = 400 cm² . . . . difference in surface area