if 0<st<1
then which of the following can be true?
a) s<-1 and t>0
b)s<-1 and t<-1
c)s>-1 and t<-1
d)s>1 and t<-1
e))s>1 and t>1
usually such problems take more time two solve for me, is there a easy procedure that must be followed to get fast at these problems?