a$)$ a $1\mathrm{.}4-$kg mass is projected from the edge of the top of a $21-$m tall building with a velocity of $31$ m$/$s at $33\backslash$deg above the horizontal. disregard air resistance and assume the ground is level. what is the speed of the mass just before it strikes the ground? m$/$s b$)$ if the mass in the above problem is projected at $55\backslash$deg above the horizontal instead, its speed just before it strikes the ground is your answer in the above problem.