Exercise 4.1.5 solution

\[\frac{5\pi}{12}\text{ rad}\times\frac{1\text{ rev}}{2\pi\text{ rad}}=\frac{5}{24}\text{ rev}\]

\[\frac{5\pi}{12}\text{ rad}\times\frac{{360^\circ}}{2\pi\text{ rad}}=75^\circ\]