Answer
The magnitude of the current induced in the loop is zero.
Work Step by Step
The current in the long wire produces a magnetic field around the wire. Since the current is changing over time, the magnitude of the magnetic field also changes.
This changing magnetic field produces a changing flux through the top half of the loop, and a changing flux through the bottom half of the loop in the opposite direction. By symmetry, the net change in magnetic flux is zero. Therefore, there is no change in magnetic flux through the loop so there is no induced emf and no induced current.
The magnitude of the current induced in the loop is zero.
