$16\mathrm{.}9$ The transactions $T$ and $U$ at the server in Exercise $16\mathrm{.}8$ are defined as follows:

$T$:$x=$read$(i)$; write $(j,44)$;

$U$: write $($i$,55)$; write$($j$,66)$;

Initial values of $a_i$ and $a_j$ are $10$ and $20,$ respectively. Which of the following interleavings are serially equivalent, and which could occur with two$-$phase locking?

$($a$)$

$\backslash$table$[[x=$read$(i)$;$,],[,],[$write $(j,44)$;$,],[,$write $(i,55)$;