According to Boyle’s law, For a fixed amount of an ideal gas kept at a fixed temperature, P (pressure) and V (volume) are inversely proportional.
Therefore,

Given
,
and
.
Thus,

Answer: Parietal
Explanation: The parietal lobe is where the primary somatosensory cortex is located. This cortex is where all tactile stimulation is processed in the brain and allows to you detect/feel someone scratching your back.
I would have to see the graph.. but by looking at one one online, they are between points D and E.