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A fixed 12.5-cm-diameter wire coil is perpendicular to a magnetic field 0.55 T pointing up. In 0.30 s, the field is changed to 0.26 T pointing down. What is the induced emf in the coil?
a) 0.013 V
b) 0.020 V
c) 0.032 V
d) 0.045 V