A space probe is traveling in outer space with a momentum that has a magnitude of 7.5*10^7kgm/s. A retrorocket is fired to slow down the probe .it applies a force to the probe that has a magnitude of 2.0*10^6N and a direction opposite to the probes motion .. it fires for a period of 12s. Determine the momentum of the probe after the retrorocket ceases to fire