Consider four processes with the following starting and ending times:

Process A: start time $6,$ end time $8$

Process B: start time $3,$ end time $5$

Process C: start time $4,$ end time $7$

Process D: start time $2,$ end time $9$

For each pair of processes, indicate whether they run concurrently $($Y$)$ or not $($N$).$

AB:

AC:

AD:

BC:

BD:

CD: