A.S+Y×T/LBP B.S+(Lt-Y)×T/LBP C.S+(Y-Lt)×T/LBP D.S+Y×LBP/T
A.Vs/Vw B.Vw/Vd C.VdVw D.Vs/Vd
A.Vs×Vd/Vw B.Vs×Vw×Vd C.Vs/Vw/Vd D.Vs×Vw/Vd