Certain rifles can fire a bullet with a speed of 965 $\mathrm{m} / \mathrm{s}$ just as it leaves the muzzle (this speed is called the muzzle velocity). If the muzzle is 70.0 $\mathrm{cm}$ long and if the bullet is accelerated uniformly from rest within it, (a) what is the acceleration (in $g^{\prime}$ s) of the bullet in the muzzle, and (b) for how long (in ms) is it in the muzzle? (c) If, when this rifle is fired vertically, the bullet reaches a maximum height $H,$ what would be the maximum height (in terms of $H$ ) for a new rifle that produced half the muzzle velocity of this one?