<B i.e. <1 = 115
<B = <ADC or angle 4 = 115 [Opposite angles of rhombus are equal]
angle 4 = angle 5 = 115[Being vertically opposite angles]
angle 6+ angle 5 = angle 8[Exterior angle of a triangle is equal to sum of two interior opposite angles]
or, 40+115 = angle 8
or, angle 8 = 155
