The answer is use the perpendicular bisectors to find the center of the circle.
39.5 i am pretty suree of it :P
<span>The term that you want is 5C2*p^2*q^3
representing 2 successes and 3 failures. This term's value is</span>
<span>(5C2)(0.5^5)
= 10*0.03125 = 0.3125 = P(2 successes in 5 trials) =31.3% </span>