Question

How many right angles are in a regular pentagon?

Answer 1

There are no right angles among interior angles of a regular pentagon.

Explanation:

If you are interested, it is easy to prove that regular `N`-sided polygon has each interior angle equal to
`phi = 180^o*(N-2)/N` (degrees.)

So in case of a regular `5`-sided polygon (pentagon) the interior angles measure at
`phi = 180^o*(5-2)/5 = 108^o`