Aflexible container at an initial volume of 8.15 l contains 6.51 mol of gas. more gas is then added to the container until it reaches a final volume of 12.7 l. assuming the pressure and temperature of the gas remain constant, calculate the number of moles of gas added to the container.

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)