Which of the following languages accurately describes the regular expression (a+b+c)(a+c) Set of strings over {a,b,c) that always ends with ' a ' Set of strings over (a,b,c) that always ends with ' a ' or ' c ' Set of strings over (a,b,c) that always ends with ' ac ' Set of strings over (a,b,c) that always begins with ' a ' or ' c ' or ' b ' QUESTION 4 Which of the following regular expressions represents the set of all strings over (a,b) that always begins with a and ends with b a(a+b)b a4b7b+a4b7a (ab+a) 3a "b*b