单项选择题
A.r=20.9m,D=60.95m B.r=20.9m,D=72m C.r=22.5m,D=60.95m D.r=22.5m,D=72m
A.135cm B.148.5cm C.190.9cm D.210cm
A.269.1kg B.248.4kg C.330.7kg D.358.3kg