As a capital letter M it has three angles
4 angles
The letter "N" as two acute angles.
It has 3 interior angles
There are no angles: the only intersections are of curves.
What angles are in the letter R
As a capital letter M it has three angles
4 angles
There are 3 right angles in the letter F
In the upper-case letter A? I see none, nor in lower case a either.
The letter "N" as two acute angles.
The letter 'H' has 8 angles. Each of the two vertical lines has two right angles, and the horizontal line has four angles (two acute angles and two obtuse angles). So, altogether, the letter 'H' has 8 angles.
It has 3 interior angles
3 right angles.
There are no right angles in the letter "e".
3 right angles, one obtuse angle
K and R are two possibilities.