T7:=REF(vol,6)/REF(VOL,7)
T6:=REF(VOL,5)/REF(VOL,6)
T5:=REF(VOL,5)/REF(VOL,4) =1.5;
T4:=REF(VOL,4)/REF(VOL,3) =1.5;
T3:=REF(VOL,2)/REF(VOL,3) =1.5;
T1:=V/REF(VOL,1)
T0:=C O AND C REF(C,1);
XG:T0 AND T1 AND (T3 OR T4 OR T5 OR T6 OR T7);