1. The problem statement, all variables and given/known data Consider the grammar S←(L) S←a L←L,S L←S draw a parse tree for the expression (a, (a, a)) 3. The attempt at a solution I cant tell if the starting symbol should be S or L. Also what do the commas mean? The examples we did in class had plus and minus signs and stuff like that but we didn't have an example of what to do when there is a comma. Also is there a difference if the parenthesis weren't there around the L in the first one?