[填空题]
The bolts on the cylinder head8s)9l/gnd odyv0d(pm- g b.no of an engine rea ig+( kc( iofc0b;*+poabn3c ,bqk5fquire tightening to a torque of 38 i;b f,nc 0 *++(o5ickfo kcabgq3 ab(p$m \cdot N$ 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