Numerical Methods: Euler to Runge–Kutta · Hard problem

A solver of unknown order $p$ (global error $\approx Ch^p$) computes $y(1)$ three times: $2.1000$ with step $h$, $2.0440$ with step $\dfrac{h}{2}$, and $2.0370$ with step $\dfrac{h}{4}$. Estimate the order $p$ from these three values.