Please put the subject of your question in the subject line. We have no idea what the subject "garyson" is about.
The radius of the ear drum is not needed for the answer.
Your question seems to already contain the answer. They tell you the atmospheric pressure on the ear at the top, and then they ask you what it is.
A person rides up a lift to a mountaintop, but the persons ears fail to pop –that is, the pressure of the inner ear does not equalize with the outside atmosphere. The radius of each ear drum is 0.40×10ˆ-2m. The pressure of the atmosphere drops from 1.010×10ˆ5 Pa at the bottom of the lift to 0.998×10ˆ5Pa at the top. What is the pressure on the inner ear at the top of the mountain?
2 answers
You want the difference in pressure, subtract.