QUESTION 7 A set of production rules that describe all possible strings in a given formal language. OA What is Denotational Semantics? OB. What is a Formal Grammar? OC. What is an Abstract Syntax Tree? What is Operational Semantics? OD. This question is about denotational semantics. Suppose that there is the following denotational semantics for a programming language. The denotations map to PostScript code. M(1) = def 1 M(2) = def 2 M(@ operand) = def M(operand) dup M(operand! operand) "der M(operands) Mloperand) add M(stmt1; stmt2) = def M(stmt1) M(stmt2) What is the evaluated meaning of 1! 2; @ 1 that is, what values would the evaluation of M(1 ! 2; @ 1) leave on the stack? Assume^ represents the bottom of the stack and $ represents the top of the stack. ^ 1 2 1$ ^ 1 2 3 $ ^3 1 $ ^ 2 1 1 $ 3 1 1 $ Using the grammar and denotational semantics below, determine the integer value generated by the string "bac". Grammar 'a' | 'b' | 'c' :: 'a' | 'b' | 'c' Semantics Mabc('a')=3 Mabc('b') = 5 Mabc('c') = 6 Mabc( 'a') = 2 * Mabc( ) + 1 Mabc( 'b') = 3* Mabc( ) +2 Mabc( 'c') = 1 * Mabc( ) +3