6.1 Angles and Their Measure/36

${\frac {\pi }{2}}^{\circ }\cdot {\frac {180}{\pi {\circ }}}={\frac {\cancel {0}}{2}}={\frac {2\pi }{3}}$

\frac{\cancel{2}\cdot \cancel{2}\cdot 2\cdot \cancel{3}\cdot \cancel{5}}{1}\cdot\frac{\pi}{\cancel{2}\cdot \cancel{2} \cdot \cancel{5} \cdot \cancel{3} \cdot 3}