Answer:
Area = πr^2/2, and Perimeter πr+2r
Explanation:
so the formula for a circle is πr^2, and a semicircle is half of a circle....... so we do the formula of a circle, πr^2, divided by 2 to get the area of it, πr^2/2. now we kind of do the same thing for perimeter. we do the circumference/2, so 2πr/2, or πr but we need to add the bottom of the semicircle so we add 2r to it . so this whole equation would be πr+2r.