Which type of scientific statement is determined as a statement of fact that is generally accepted to be true and universal because it has always been observed to be true?

Law, if you notice when reading about the laws of physics it is stated as a fact and has been accepted as the truth.

For example : Newton's first law of physics

"An object in motion tends to stay in motion until an object of an opposite force and direction acts upon it."

hope this helps have a nice day

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a