A circular coil of wire 8.40 cm in diameter has 18.0 turns and carries a current of 2.80 A. The coil is in a region where the magnetic field is 0.650 T. What is the magnetic moment of the coil?

a) 0.074 A m²
b) 0.148 A m²
c) 0.296 A m²
d) 0.592 A m²