The velocity of a polar bear is given by vector u $=(-16\mathrm{.}5$ km$/$h$,-11\mathrm{.}1$ km$/$h$).$ Part $($a$)$How fast is the polar bear moving, in km$/$h$?$ Part $($b$)$In what direction is the polar bear moving? Express your answer as an angle measured in degrees below the negative x$-$axis.