The throttle-control lever OA rotates in the range 0 <>() <>90°. An internal torsional return spring exerts a restoring moment about O given by M = K(() + 1r /4), where K = 500 N · mm /rad and () is in radians. Determine and plot as a function of () the tension T required to make the net moment about O zero. Use the two values d = 60 mm and d = 160 mm and comment on the relative design merits. The effects of the radius of the pulley at B are negligible.