6. (10 points) Classify each of the languages below using one of the following categories: Regular (R) and Non-regular (NR). You do not need to justify your answer. Language R/N 1 { x over {a, b}* | x is nonempty and [x] is divisible by 5} 2 { x over {a, b}* | x has the same count of a's and bs} 3 {a' bc | r0} 4 {abct | r = 2k, k,t> 0 and 0