Question

Imagine that the central bank of an economy with unemployment doubles its money supply. In the long run, full employment is restored and output returns to its full employment level. On the (admittedly unlikely) assumption that the interest rate before the money supply increase equals the long-run interest rate, is the long-run increase in the price level more than proportional or less than proportional to the money supply change? What if (as is more likely) the interest rate was initially below its long-run level?