Find context free grammars for the following languages (a) L = {a"3":n, m> 0 and n #m} (b) L = {a"l":n>m > 0 or m > k>0} (c) L = {a"bmckin+m>k>0} (d) L = {w E {a,b,c}* : n(w) = na(w) +ne(w)}