Answer:
10) 25π OR 78.5398...yd 11) 1/4π OR 0.785398...ft 12) 100π OR 314.159265....in
Explanation:
area of a circle = πr^2 (π x radius squared)
the radius is just half the diameter
so for eg:
number 10)
diameter = 10 yd so radius = 5 yd
5 squared = 25
π x 25 yd = 25π OR 78.5398...yd
i hope this helped :)