A person throws an object downwards from the top of a building. The building is 21.4 m high. The object hits the ground at the base of the building with a velocity of 22.5 m/s. Calculate the time taken between the object been thrown and hitting the ground.An object is propelled upwards from the ground at the base of 15.5 m high flat roofed building with an initial velocity of 24.8 m/s. It travels upwards and then falls back down, landing on the roof of the building. Hin (a) Calculate the maximum upward displacement relative to the ground. (Use upwards as the positive direction.) select units v Hint: (b) Determine the time taken to reach the maximum upward displacement. select units v Hint: (c) Determine the total time from the launch of the object until it lands on the roof of the building. select units vA truck is accelerated by a constant force of 4.0 kN. Its velocity increases from 37 km/hr to 58 km/hr in a time of 9.9 s. Calculate the mass of the truck in SI units. select units