Respuesta :

Answer:

m∠B = 141°

Step-by-step explanation:

sides of polygon (n) = 7

sum of angles of polygon = {(n - 2) * 180°}

= {(7 -2)*180°}

= 5* 180°

= 900°

Now,

m∠B = 900° - 148° - 142° - 130° - 129° - 120° - 90°

m∠B = 141°