Csc (x) = sec ( 90 - x) so csc(52) = sec (90 - 52) = sec (38)
So basically, each number is equal to the two numbers below it added together.
See, 7 = 3+4, 8 = 5 +3, etc.
So, the top would be 16 + 17.
16 + 17 = 33
So 33 goes on top.
The surface area of a sphere is 4r^2pi, so dividing 100 by 4pi gives a result of 25/pi. Taking the square root and rationalizing the denominator, we have 5sqrt(pi)/pi as the radius of the sphere.