$6\mathrm{.}3.$ Figure $6\mathrm{.}28$ shows a computation of processes $P,Q,$ and $R$ using asyn$-$

chronous communication. The messages in this computation are $p1q1,$

$r1q2,q3p2,p3q4,$ and $r2q5.$

$($a$)$ Determine the integer timestamp of each event in the computation

above.

$($b$)$ Determine the vector timestamp of each event in the computation

above. Each vector timestamp has three elements, with the first, sec$-$

ond, and third elements indicating logical clock values for $P,Q,$ and

$R,$ respectively.

$($c$)$ Indicate all of the events that are concurrent with P$3.$

$($d$)$ Indicate all of the events that are concurrent with R$2.$