No, it must be obtuse.
When it is larger than 90 degrees.When it reaches 90
yes it can
A complement of an acute angle must be an acute angle. An acute angle is an angle whose measure is more than 0 degrees but less than 90 degrees. For example, even if the angle was the minimum 1...
The word acute refers to angles, not sides. It does have all three angles are acute (less than 90°)