If the chain is lowered at a constant speed v = 1.2 m/s, determine the normalreaction exerted on the floor as a function of time. The chain has a mass of 80kg and a total length of 6 m.a) (16t + 9.8) N vertically upwardb) (16t + 9.8) N vertically downwardc) (16t + 19.2) N vertically downwardd) (16t + 19.2) N vertically upward