just need to answer (e , f , g )

5. Prove that the following languages are not regular (a) L = {a"bak : k-n +1). (b) L = {a"bak : k n +1). (c) L = {an blak : n = l or l k} Chapter 4 Propertics of Regular Lauge Chapter 4 Properties of Regular Languages (d) L = {anl/ : n > 1). (e) L= {w: na(w)nb (w)). (f) L = {ww : w E {a,b)')