Final answer:
The impulse of the object is 72 Ns (Newton-seconds).
Step-by-step explanation:
The impulse of an object is the change in momentum experienced by the object. It can be calculated by multiplying the net external force applied to the object by the time over which the force is applied.
In this case, the external force is 9 N and the time is 8 s. Therefore, the impulse can be calculated as follows:
Impulse = Force x Time = 9 N x 8 s = 72 Ns (Newton-seconds)