[填空题]
The bolts on the cylinder0eps3 3y hbs-v head of an engwqi* :u/y fop5ine require tightening to a torque of 38/y:*qp ofu5wi $m \cdot N$ 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