find the measure of the arc?

Measure of the arc EF = 146°

The angular distance of an arc is always equal to the measure of its central angle.

Since the central angle is 146° that means that both arcs EF and AB have the same angular distance of 146°.

Note: They would have different values (based on their radius) if you wanted the *length* of the arc. But this is asking for the measure in degrees which implies an *angular* distance.

The measure of arc EF equals 146 degrees.