an airline employee tosses two suitcases, of weight 30 lb and 40 lb, respectively, onto a 50 lb baggage carrier in rapid succession. knowing that the carrier is initially at rest and that the employee imparts a 9 ft/s horizontal velocity to the 40 lb suitcase, determine the final velocity of the baggage carrier if the first suitcase tossed onto the carrier is (a) the 30 lb suitcase, (b) the 40 llb suitcase