A force F $=(4\mathrm{.}2$N$)$i $-(9\mathrm{.}8$ N$)$k acts on an object of mass $1\mathrm{.}00$ kg as it moves in the y direction at a speed of $7\mathrm{.}45$ m$/$s$.$ At this instant, what is the rate at which the force is doing work?