Consider the following statements: $S_1:\{(a^n)^m|n\leq m\geq0\}$ $S_2:\{a^nb^n|n\geq 1\} \cup \{a^nb^m|n \geq1,m \geq 1\} $ Which of the following is regular? $S_1$ only $S_2$ only Both Neither of the above

Which of the following is a non-regular language? $L = \{wxwy \mid x,y,w \in (a+b)^+\}$ $L = \{xwyw \mid x,y,w \in (a+b)^+\}$ $L = \{wxyw \mid x,y,w \in (a+b)^+\}$ All of these