size(7cm,0); import solids; currentprojection = orthographic(50,50,25); real r=4, h=7; triple pO=(0,0,0), pS=(0,0,h), pA=(r,0,0); revolution CoRev=cone(pO,r,h,axis=Z,n=1); draw(CoRev,1bp+blue); draw(pS--pA); draw(pS--pO^^pO--pA,dashed); label("$S$",pS,N); dot(Label("$O$",align=SE),pO); dot(Label("$A$",align=SW),pA);