AB AB 1-BD 1-BD X Z E 1-BD -BD ABC ABC T=w/x-= 1-BD CE 1-BD-CE 1-BDx z w C BD AB 1- BD E 1- x z w C BD AB 1- BD E 1- C z' BD CE ABC BD CE BD ABC T w x - - = - - - = == 1 1 1 1