1、3.14×2r+2r=41.4 8.28r=41.4 r=5(cm)得长方体的宽=5cm,长=41.4÷2﹣5=15.7(cm),高=6cm长方体的表面积=(15.7×5+15.7×6+5×6)×2=202.7(cm²)圆柱的体积=3.14×5²×6=471(cm³)2、r=9.42×2÷3.14=6(cm)d=12(cm)圆柱侧面积=3.14×12×5=188.4(cm²)圆柱体积=3.14×6²×5=565.2(cm³)