A Slanted Roof Rises at ° Above the Horizontal

Short Answer

A slanted roof rises at ° above the horizontal, and the straight-line distance from the top
of the roof to the bottom edge is 4.5 m. The roof is covered with ice, so it offers no friction
to objects sliding on it. A piece of ice at the top suddenly breaks loose and begins to slide
down from rest.
(a) How long will it take for the ice to reach the bottom edge of the roof?
(b) How fast will the ice be traveling just as it reaches the bottom edge?