2. (a) Insert the full parentheses in SK'?/r. Note here that you should write S, K, ? and / in full. (1.5) (b) Give all closed subterms of SK?/r writing the largest subterms (those with more symbols) first. Here, keep all the subterms as compact as possible and do not expand them as you did in the previous question. You should work out which term has more symbols than another even if the terms are written compactly, for example: ?/ has more symbols than ?/ although they are each written compactly with two symbols (this is because / has more symbols than I). (1.5)