A large rocket has a mass of 2.26 x 106 kg at takeoff, and its engines produce a thrust of 3.83 x 107 N. (a) Find its initial acceleration (in m/s : (b) How long does 2) if it takes off vertically. (Enter the magnitude.) m/s2 it take (in s) to reach a velocity of 289 km/h straight up, assuming constant mass and thrust? S