Given data:
* The acceleration of the elevator is,

* The initial velocity of the elevator is u = 1.2 m/s.
* The time taken by the elevator is t = 4 seconds.
Solution:
By the kinematics equation, the final velocity of the elevator is,

where v is the final velocity,

Thus, the final velocity of the elevator in the upward direction is 28.72 m/s in the upward direction.