choose the right answer

Question B12 If A and B are languages with m and n strings respectively does it follow that A.B has mxn strings? ("mxn" means "m times n") a) b) c) d) No, it is not true because at least there is a counter example, A= B = {1, a). No, it is not true when both A and B are empty set No, it is not true when A - B. Yes. Question B13 How many of the following languages can be defined by Finite Automata? {ab, aabb, aaabbb, aaaabbbb, aaaaabbbbb.... (abb, aabbbb, aaabbbbbb, aaaabbbbbbbb, ......} {a, aa, aba, abba, abbba, abbbba, abbbbba, ......) (a, bab, bbabb, bbbabbb, bbbbabbbb, ......) 1 2 a) b) c) d) 3 4