Answer:
B = 47°
Explanation:
THe theorem to solve this is very simple. The angle created Angle B intercepts to arcs, one major, another minor.
The major arc is DE, 142 degrees.
The minor arc is AC, 48 degrees.
The two secants intersect outside the circle and creates a vertex angle, Angle B. The theorem tells us that the measure of that vertex angle would be ONE HALF of the difference of the two intercepted arcs. So, we have:

So, B = 47°