(a) Strings over the alphabet {a,b,c} where the ﬁrst a precedes the ﬁrst b Answer: ab*(c*|ε) (B)/>/> Comments consisting of a string surrounded by /* and */ Answer: /* (a*|b*|c*)* */ (c) All strings of 0’s and 1’s with an even number of 0’s , with at least two 0’s. Answer: (1*01*01*)* (d) {w ∈{a,b}*|w starts with a and contains bba as a substring } Answer: ( a|b )* bba ( a|b )* (e) {w ∈{0,1}*|w contains 111000 as a substring } Answer: (0|1)* 111000 (0|1)* (f) {w ∈{0,1}*|w consists of alternating 0’s and 1’s } Answer: (010 | 101)*

Really not sure of any of my answers, if anyone can correct me if I'm wrong before I submit my answers I will be very grateful.