Vector has magnitude $15\mathrm{.}0$ m$,$ and direction $81\mathrm{.}0$ counterclockwise from the positive$-$x axis. Vector can be expressed as $=(11\mathrm{.}0-18\mathrm{.}0)$ m$.($a$.)$ What is the magnitude of $?2233\mathrm{.}9$ m $($b$.)$ What is the angle of $,$ in degrees counterclockwise from the positive$-$x axis?