The answer says it's 0 but I don't understand which direction is the magnetic field.
Use the Equations:
1) Magnetic Flux= Area of Loops x B x ( Magnetic Field).
2) Magnetic Flux= Area Loops x B x cos
Since the magnetic field is perpendicular to the plane of loops, no a, so use equation 1 *Dont forget to convert
MF = 0.0004 volts/sec