m∠1 = _°
•70
•50
•90

Answer:
50°
Step-by-step explanation:
By intersecting secants theorem:
[tex]m \angle \: 1 = \frac{1}{2} (140 - 40) \degree \\ \\ m \angle \: 1 = \frac{1}{2} \times 100 \degree \\ \\ m \angle \: 1 = 50 \degree [/tex]