What would happen if the relative concentrations of oxygen inside the lung and in the blood become equal to each other?

As the intercostals the lungs do expand. the lung's expansion causes pressure in the lungs to become slightly negative relative to atmospheric pressure. Air moves from an area of higher pressure to an area of lower pressure. thank you for this question. it is definitely a good one. i hope i was able to answer it.

Some of her  assignments would be creation of drugs. she is a medical chemist after all so she'd need to have the necessary knowledge to make medicine which can later be sold in a pharmacy