In commerce, liquid oxygen is classified as an industrial gas and is widely used for industrial and medical purposes. Liquid oxygen is obtained from the oxygen found naturally in air by fractional distillation in a cryogenic air separation plant.
Lesson Summary. An acute angle is any angle smaller than 90 degrees. A right angle is an angle that measures 90 degrees. It doesn't matter how much smaller the angle is than 90 degrees; as long as it's smaller, it's acute. To unlock this lesson you must be a Study.com Member.
A right angle is an angle with measure equal to 90 degrees. An acute angle is an angle with a measure between 0 and 90 degrees. An obtuse angle is an angle with a measure between 90 and 180 degrees. Two angles are complementary if the sum of their measures is equal to 90 degrees.