Answer
The eardrum is moving outward during the following time intervals:
$(0.00455, 0.00909)\cup(0.01364, 0.01818)\cup (0.02273, 0.02727)$
Work Step by Step
When the pressure is positive, the eardrum will be pushed inward.
When the pressure is negative, the eardrum will be pulled outward.
We can use the graph to determine the time intervals when the pressure is negative:
$(0.00455, 0.00909)\cup(0.01364, 0.01818)\cup (0.02273, 0.02727)$
The eardrum is moving outward during the following time intervals:
$(0.00455, 0.00909)\cup(0.01364, 0.01818)\cup (0.02273, 0.02727)$