Sti ca V=πR²h, deci πR²8=128π: R²=128π/8π; R²=128-8; R²=120; R=√120; R=2√30
Ab=πR²; Ab=120π(cm²)
Al=2πRG, dar la cilindru H=G, deci Al=2*π*2√30*8; Al=32√30π(cm²)
At=Al+2Ab; At=32√30π+2*120π=32√30π+240π
√30 aproximativ = 5,47
At=32*5,47+240=175+240=415π(cm²)