3. (10 points) Consider the language L = {uw | u and w are strings over {0,1} and have the same number of 1s} (a) Prove that L = {ve {0,1}* | v has an even number of 1s}, and that L is a regular set. (b) Prove that the language L' = {uow | u and w are strings over {1} and have the same length} is not regular