LSA of cone: πra (where r is the radius and a the apotheme).
Ok, let's start.
You have the diameter (look at that dotted line at the base), that it is the double of radius.
If d = 2r, then r = d/2
r = 10/2 = 5 yd.
Now, we can calcate the LSA.
π*5*12.1 = 60,5π yd.² = 60,5*3,14 = 189,97 yd.²
Answer D
