[填空题]
The bolts on the cylinder hea)2oysmp* *h eqd of an qp0tag57+d2igxwbl xl37 3sn engine require tightening to a torque of 38+ngpg33 ls5a2wxt7dxilbq0 7 $m \cdot N$ If a wrench is 28 cm long, what force perpendicular to the wrench must the mechanic exert at its end? N If the six-sided bolt head is 15 mm in diameter, estimate the force applied near each of the six points by a socket wrench (Fig. 8–41). N