Answer:
∠B = 141
Step-by-step explanation:
n - > number of sides
n = 7
Sum of all interior angles = (n -2 ) * 180
= 5 * 180 = 900
∠B + 148 + 90 + 142 + 130 + 129 + 120 = 900
∠B + 759 = 900
∠B = 900 - 759 = 141
