what was the average speed, in km$/$h$,$ of a boat that moves $16\mathrm{.}0$ km across a lake in $45$ min?

A$.0\mathrm{.}0059$ km$/$h

B$.0\mathrm{.}36$ km$/$h

C$.2\mathrm{.}8$ km$/$h

D$.21\mathrm{.}3$ km$/$h

E$.110$ km$/$h