You’ve just discovered a new X-ray binary, which we will call Hyp-X1 ("Hyp" for hypothetical). The system Hyp-X1 contains a bright, B2 main-sequence star orbiting an unseen companion. The separation of the stars is estimated to be 20 million kilometers, and the orbital period of the visible star is 4 days. A.) Use Newton’s version of Kepler’s third law to calculate the sum of the masses of the two stars in the system. (Hint: See Mathematical Insight Measuring Stellar Masses in the textbook) Give your answer in both kilograms and solar masses(MSun=2.0×1030kg)(MSun=2.0×1030kg). Express your answer in kilograms to two significant figures. B.) Express your answer as a multiple of Sun's mass to two significant figures. C.) Determine the mass of the unseen companion.(Hint: A main-sequence star with spectral type B2 has a mass of about 10MSun.10MSun.) Express your answer as a multiple of Sun's mass to two significant figures. D.) Is it a neutron star or a black hole?