k=4×90=360 degrees
Angle for 8 spokes = 360/8 = 45 degrees
Angle for 10 spokes = 360/10 = 36 degrees
Angle for 12 spokes = 360/12 = 30 degrees
(i) As with increasing number of spokes the angle is decreasing so they are in inverse proportion
(ii) Required angle = 360/15 = 24 degrees
(iii) Number of spokes needed = 360/40 = 9 spokes