I just need g

Find context-free grammars for the following languages (with n 0,m0). (a) L={anbm:nm+3}. (b) L={anbm:n=m1}. (c) L={anbm:n=2m}. (d) L={anbm:2nm3n}. (e) L={w{a,b}:na(w)=nb(w)}. (f) L={w{a,b}:na(v)nb(v), where v is any prefix of w}. (g) L={w{a,b}:na(w)=2nb(w)+1}