&G )T,P.nc ap T.ng.nc P at T,nB,nc onB T.P.nc 15 15 B C C B C T n n T P n B T n n B P n G P , , , , , , ] ( ) ( ) [     =   C B C T P n B T n n n P G , , , , ] ( ) [     = T P nC nB V , , ( )   = =VB