Arrange the following in decreasing order of priority for functional groups of organic compounds:
$(a) -NH_2, -OH, -CN, >C=O, -C \equiv C, >C=C < $
$(b) >C=O, -CHO, -COCl, -COOH, -COOR, -CONH_2, -CN$
$(c) -SO_3H, -CN, -COR, -C \equiv C, >C=C < $

(N/A) The decreasing order of priority is: $-CN > >C=O > -OH > -NH_2 > >C=C < > -C \equiv C$
$(b)$ The decreasing order of priority is: $-COOH > -COOR > -COCl > -CONH_2 > -CN > -CHO > >C=O$
$(c)$ The decreasing order of priority is: $-SO_3H > -CN > -COR > >C=C < > -C \equiv C$