Write each of the following in exponential form: `a\ x\ a\ x\ a\ x\ a\ x\ a\ x\ a\ x\ a` `a\ x\ a\ x\ a\ x\ a ..10\ t i m e s` `17\ "x"\ x\ "x"\ x\ "x"\ x\ y\ "x"\ y\ "x"\ y` `y\ x\ y\ x\ y\ x\ y\ x\ y ..20\ t i m e s` `7\ x\ a\ x\ a\ x\ b\ x\ b\ x\ b\ x\ c` `13\ x\ p\ x\ p\ x\ p\ x .7\ t i m e s\ x\ q\ x\ q\ x\ q .12\ t i m e s`