At a constant temperature, the volume of a gas doubles when the pressure is reduced to half of its original value. this is a statement of which gas law? boyle’s law charles’s law gay-lussac’s law combined gas law

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)