Surface area: 3. 14×0.5? ×2+6.28= 7.85(m？ )

(2) lateral area: 6×3. 14×5= 94.2(cm? )

Surface area: 3. 14×(6÷2)? ×2+94.2= 150.72(cm？ )

(3) lateral area: 6.28× 1= 6.28 (dm? )

Surface area: 3.14× (6.28÷ 3.14÷ 2)? ×2+6.28= 12.56(dm？ )

4.3. 14×( 12.56÷3. 14÷2)? ×2+ 12.56×5= 87.92(cm？ )

5.3. 14×(6÷2)? ×2+6×3. 14×20= 433.32(cm？ )& lt450cm？

A: 450 square centimeters of material is enough to make such a stationery bag.

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