2. Circumference: 3. 14× 6 = 18.84 (cm) 18.84× 2 = 37.68 (cm).

Area: 6× 6 = 36 (square centimeter) 3× 3. 14 = 28.26 (square centimeter) 28.26× 2 = 56.52 (square centimeter) 36+56.52 = 92.52 (square centimeter).

3.63×3. 14 = 179.82(cm) 179.82cm = 1.9782m 1978÷ 1.9782≈ 1000。

4.628× 0.6 = 376.8 (m) 376.8 ÷ 3. 14 ÷ 2 = 60 (m) 3.14× 60 =1304 (.