3. Find a REGULAR EXPRESSION corresponding to each of the following. (a) (we(a,b)" l#a(w) 31 (b) (xe (0,1 | x has no two consecutive 0's and no two consecutive I's) (c) All strings over 0,1,2,3,4,5,6,7,8,9) such that the final digit has appeared before. (d we 0,1,2)*w starts with a 2, ends with a 1, and contains an even number of O's). For example, both 201100201 and 211 are in the language. (e) The set of all signed or unsigned integers and real numbers in decimal notation. No leading zeros should be generated and real numbers must have at least one digit on both sides of the decimal point. For instance, 3, +3,-3, 0, +0,-0, 0.328, 1009.46, +100.80, and -100.3 are in the language, but 123., .25, +, , 003 are not