Find the length of the radius of a circle with a center at -7+2i and a point on the circle 33+11i

Hello : 
let : z = -7+2i    and  z' = 33+11i         z - z' = 40 +9 i 
the radius of a circle : |z - z' | = √((40)²+(9)²) =√1681 = 41

10 will be the number of adult tickets and 11 will be the number of children tickets. i hope i could ! good luck : )

For the first question the answer is a, for the second c, for the third d, for the 4th b, for the 5th a