$)$ By using X$,$ Y$,$ C and Z values, how much time does it take to call the timer function $($timer$\_$int$())?(5$p$)$ b$)$ With the same X$,$ Y$,$ C and Z values in part a$,$ how much time does it take to make the ctrButton variable to zero $($line $20$ in code$)?(5$p$)$