Air drag and acceleration (not gravity)

[Unstoppable13]

In physics class we made a rocket and test fired it. Now we are given the thrust and we found out the max height of the rocket and the time of flight.

Max Height = 76m
Time of thrust/ upward acceleration = .8s
Time of flight with only gravity acting until velocity is 0 . = 4.96s (not including downward fall)
Mass of rocket = 0.08 kg
Fg= 0.8N
g= 9.8m/s^2

Now we are supposed to find the air drag acting on the object. But I have no clue on how to do that because all the formulas relate to velocity, which is not really a given because the rocket is accelerating upwards. So is there a formula that I can use to solve this?

 

[DaveC426913]

The rocket is not accelerating upwards during this phase:

Time of flight with only gravity acting until velocity is 0 . = 4.96s (not including downward fall)

 

[Unstoppable13]

The rocket is not accelerating upwards during this phase:

4.96 seconds is the time it took for velocity to be 0, ... reach maximum height