Sirius (A) has white dwarf companion star Sirius (B). The system is known to have a semi-major axis of 20 au and a period of 50 years. Doppler shiftsshow that at any given time Sirius (B) moves twice as fast as Sirius (A). What is the mass of Sirius (A)? What is the mass of Sirius (B)?

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)

How many grams of phosphorus are contained in 5.09 moles of phosphorus?

What is the rate law for the uncatalyzed reaction?