1. Give a context-free grammar for each of these languages. (a) The language of all strings of the form a'b such that i 22j (b) The language of all algebraic expressions over the variables r, y, z with the operators of addition +, subtraction - multiplication *, exponentiation**, and negation - and with parentheses c) Binary numerals for positive multiples of 3, where leading zeros are not allowed. Can you do this with only three variables? Your grammar must have only one variable, the start symbol