Option C:
The measure of ∠1 is 31°.
Solution:
Measure of intercepted arc = 37°
Measure of vertical arc = 25°
If two chords intersect inside a circle, then the measure of the angle formed is one half the sum of the measure of the arcs intercepted by the angle and its vertical angle.
![$\Rightarrow \angle 1 = (1)/(2) (37^\circ+25^\circ)](https://img.qammunity.org/2021/formulas/mathematics/high-school/j40kruice92eleittnd3uuocl6t2xf51d1.png)
![$\Rightarrow \angle 1 = (1)/(2) (62^\circ)](https://img.qammunity.org/2021/formulas/mathematics/high-school/mn4i8rvrh8uyft283aedtxbywjc26j5y3g.png)
![$\Rightarrow \angle 1 =31^\circ](https://img.qammunity.org/2021/formulas/mathematics/high-school/749g2n3w6rcsh0qenbp03fcefxtna9f808.png)
The measure of ∠1 is 31°.
Option C is the correct answer.