Answer:
The height of the object after 3 seconds is 45 feets.
Explanation:
The height of an object thrown into the air with an initial upward velocity of 63 feet per second is given as

Where, h(t) is height of the object in feet and t is the time in seconds.
We have to find the height of the object after 3 seconds. So, substitute t=3.




Therefore height of the object after 3 seconds is 45 feets.