[填空题]
A 12-kg hammer strikes a nail a3i n,a-3o4yr5 rv fyoaz0es*bt a velocity of 8.5m/s and com50d /4 wfexkm2q; jr5qw8 vgewes to rest in a time interval of 8.0 ms. (a) What is the impulse given to the qe554v ek;gw2 8frw0q wx/dmj nail? kg*m/s
(b) What is the average force acting on the nail? N