3. Construct right- and left-linear grammars for the language generated by the following reg- ular expression: r = (aab*ab)* 4. Construct a context-free grammar for the lan- guage: {a'wc : i # j or j #k} that is the language of strings of a's followed by b's followed by ds, such that there are ei- ther a different number of a's and b's or a dif- ferent number of b's and d's, or both