1. (5 points) We have the following grammar with the start symbol -> -> | + I - 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 (a) Show a leftmost derivation for the expression "7+ 4- 5'; show every step. (b) Show a right most derivation for the above expression; show every step. (c) Show two different parse trees for the above expression d) The grammar is ambiguous. Show a new grammar that removes the ambiguity and makes "+" and "-" left-associative. Show the parse tree for "7 + 4 - 5" in your new grammar. Argue why this is the only parse tree in the new grammar. (e) Show a new grammar that removes the ambiguity and makes "+" and "_" right-associative. Show the parse tree for "7 + 4 - 5" in the new grammar