B1. 1) ∠NOK = 13∠MOK, ∠NOK, ∠MOK - ?

1. ∠NOK = 13∠MOK. Let ∠MOK = x, then ∠NOK = 13x.
2. ∠NOM = ∠NOK + ∠MOK = 13x + x = 14x.
3. If ∠NOM = 150°, then 14x = 150°, x = 150°/14 = 75°/7. ∠MOK = 75°/7, ∠NOK = 13 * 75°/7 = 975°/7.