$(30$ points$)$ Timer Interrupt Programming a$.(10$ points$)$ Loading the PIT counter with a value of $23864($or $0\backslash$times $5$ d$38)$ will generate an interrupt $($a every $20$msec. $1$ tick $=20$msec $($millisecond$)$ I downcount $=0\mathrm{.}84$ usec $($microsecond$)$ If we use this PIT counter value to measure time as in mp#$4,$ what is the time between event A ends and event B ends in the diagram? You are expected to show not only the final results, but also the calculation steps. b$.(10$ points$)$ What value should the PIT counter be loaded to generate an interrupt every $5$msec $?$ Explain why.