Finding gamma from measured pressures

Air in a pump is squeezed quickly, and its pressure is read at six volumes. You will make the program find $\gamma$ from the readings, using a straight-line fit, and predict the pressure at $1.0\ \text{L}$.

The idea. For an adiabatic change $pV^\gamma$ is constant, so $\ln p = -\gamma\ln V + \text{constant}$. A graph of $\ln p$ against $\ln V$ is a straight line whose slope is $-\gamma$.

Your tasks.

1. Work out x, the logarithms of the volumes, and y, the logarithms of the pressures.
2. Fit a straight line, a and b, and read off gamma.
3. Predict the pressure at $1.0\ \text{L}$, where $\ln V = 0$.