3. (5 marks) Show how to define the following languages over ={0,1} using only , the alphabet symbols 0 and 1 , and the operations of union, concatenation, and closure. Note: Your answer cannot use the intersection or complementation operation. Below "or" always means "inclusive or". (a) All strings that have both 000 and 111 as a substring. (b) All strings that have 0000 or 1111 as a substring. (c) All strings that do not have 111 as a substring. (d) All strings of odd length that have 0000 as a substring. (e) All strings w satisfying condition (i) or condition (ii): (i) w has at most three occurrences of 0 ; (ii) w has at most three occurrences of 1