Geometry Essentials · Superchallenge problem

A protractor has rays drawn from its centre $O$ to the $19$ marks $0^\circ, 10^\circ, 20^\circ, \ldots, 180^\circ$. Two angles formed by these rays are adjacent if they share a vertex and a side and have no interior points in common. How many pairs of adjacent angles formed by these rays are complementary or supplementary?