$15.(3$ points$)$ We are sorting $($non$-$decreasingly$)$ an array of $8$ integers usiag heapsort, and we thave juer finished a reheapification downward $(\text{'}$heapifying semiheap". The array now looks like this:How many reheapifications downward have been performed so far? $($Check only $1.)$Note $1$: We have used "reheapifying downward" and "beapifying a semiheap" interchangeably.Note $2$: Count only the "reheap"s done after array has already been transformed into an initial beap$\mathrm{.}1\mathrm{.}2\mathrm{.}034\mathrm{.}056.$