Consider a simplified CFG for the set language:

(1) exp ? exp MINUS term (2) | term (3) term ? term UNION factor (4) | factor (5) factor ? LPAREN exp RPAREN (6) | LCURLY LIST RCURLY 

Note: lower-case symbols are nonterminals, upper-cases symbols are terminals

Answer the following questions related to LR parsers, show all works of how you get these answers.

a. Write all possible items for production rule (5): factor ? LPAREN exp RPAREN

b. I₁ = { term ? term UNION . factor }. Find out Closure(I₁)

c. I₂ = { factor ? LPAREN . exp RPAREN }. Find out Closure(I₂)

d. I₃ = { exp ? . exp MINUS term; exp ? exp . MINUS term ; exp ? exp MINUS . term }, X = MINUS. Find out Goto(I₃, X)