$\varepsilon=\frac{-\frac{d\left(\frac{L}{K}\right)}{\frac{L}{K}}}{\frac{d\left(\frac{n}{R}\right)}{\left(\frac{w}{R}\right)}}=-\frac{d \log \left(\frac{L}{K}\right)}{d \log \left(\frac{w}{R}\right)}$

$L=12+\frac{M}{2w}$