2.13 Give regular expressions describing the following languages. In all cases, the alphabet is {0, 1). 1. {w : w contains at least three 1s) 2. {w : w contains at least two 1s and at most one 0), 3. w wcontains an even number of Os and exactly two 1s). 4. w w contains exactly two Os and at least two 1s. 5. fw : w contains an even number of Os and each 0 is followed by at least one 1) 6. w every odd position in w is 1