b$)$ what is the difference between the execution of the following two programs? Please explain the reasons. After that, please fix the problems of line $9$ and line $10$ of the $1$st program so that the two programs have no running difference import concurrent.futures def thread $($num$,$ t$)$: print$("$Thread $\%$s started" $\%$num$)$ time.sleep$($t$)$ with concurrent.futures.ThreadPoolExecutor$()$ as t: t$.$submit$($thread$(1,3))$ t$.$submit$($thread$(2,6))$ import concurrent.futures def thread $($num$,$ t$)$: print$("$Thread $\%$s started" $\%$num$)$ time.sleep$($t$)$ with concurrent.futures.ThreadPoolExecutor$()$ as t: t$.$map$($thread$,(1,2),(3,6))$