1.Develop leftmost and rightmost derivations respectively for the Identifier value ab56c78, using the following BNF syntax:

Identifier -> Identifier { Letter | Digit } | Letter

Letter -> a | b | | z | A | B | | Z

Digit -> 0 | 1 | | 9

2.Write the following statements as a series of Prolog facts and rules:

Mammals have four legs and no arms, or two arms and two legs. A cow has no arms.

Can Prolog derive the conclusion that a cow has four legs? How do you improve your answer so that it rules out cows with 2 arms?