For this case, we have that by definition, similar triangles are those that have the same shape but do not necessarily have the same size. When two triangles are similar, the corresponding angles are congruent and their corresponding sides are proportional.
That said, the angle S measures 102 degrees.
So, we know that the sum of the internal angles of a triangle is 180:
![36 + 102 + R = 180\\R = 180-102-39\\R = 39](https://img.qammunity.org/2020/formulas/mathematics/high-school/xo015ivu8vd7th9lcz0dktb1fca4rtbc5m.png)
Thus, angle B is 39 degrees.
Answer:
Option A