2, (3+4=7 points) Give CFGs that generate the following languages. Your CFGs should have at (a) Li-ful w is a balanced string of parentheses and brackets). The alphabet here is - (b) L2 is the collection of all strings that contain at least one 1 in their second half (if the most 2 variables. Unless specified otherwise, the alphabet is = {0,1} string is of odd length, we exclude the middle symbol to construct the second "half"). In other words, L2 (uu I u E ., . 1 and lul lul}