[填空题]
A hammer thrower accelxz7rg*mz 6.p f-gb /2g n-4tfwj 8eoeuerates the hammer from rest within four full turns (ymfg :voc:1;d ew6*/nrkujd0ds e- 8p revolutions) and releases it at a speed of 28 c wn0-d1;d/d68ef::op j*ver sgkyu m$m/s$ Assuming a uniform rate of increase in angular velocity and a horizontal circular path of radius 1.20 m, calculate (a) the angular acceleration, $rad/s^2$ (b) the (linear) tangential acceleration, $m/s^2$ (c) the centripetal acceleration just before release, $m/s^2$ (d) the net force being exerted on the hammer by the athlete just before release, N (e) the angle of this force with respect to the radius of the circular motion. $^{\circ} $