Sосн=(1/2)*ab*bc*sin(B)=(1/2)*20*13,5*sin(30)=(1/2)*270*(1/2)=67.5
V=(1/3)*Vосн*H=(1/3)*67,5*2.2*100=4950 см^3
Sосн=(1/2)*ab*bc*sin(B)=(1/2)*20*13,5*sin(30)=(1/2)*270*(1/2)=67.5
V=(1/3)*Vосн*H=(1/3)*67,5*2.2*100=4950 см^3