Ninety degree , less than ninety degree and more than ninety degree are the three measures.
Explanation
When a triangle is having an an angle that is ninety degree it is known as the right angle .
When the other angle of the triangle is having measure less than ninety degree it is known as acute angle ( the angles can be forty five degree, sixty degree, all the angles must be less than ninety).
When the third angle of the triangle is more than ninety degree it is known as the obtuse angle( the angles can be one twenty degree, one eighty degree, all the angles must be greater than ninety.)