#### Example A.29.

From the graph of atmospheric pressure, estimate the following:

- The atmospheric pressure measured at an altitude of \(15,000\) feet
- The altitude at which the pressure is \(12\) inches of mercury

## Solution.

- The point with first coordinate \(15,000\) on the graph at right has second coordinate approximately \(17.4\text{.}\) We estimate the pressure at \(15,000\) feet to be \(17.4\) inches of mercury.
- The point on the graph with second coordinate \(12\) has first coordinate approximately \(25,000\text{,}\) so an atmospheric pressure of \(12\) inches of mercury occurs at about \(25,000\) feet.