This double star system is observed to complete one revolution in 35 yr. What is M2?

This double star system is observed to complete one revolution in 35 yr. What is M2?(For comparison, the distance from the sun toEarth is about 1.5 × 1011 m, and the mass ofthe Sun is about 2 × 1030kg.) This methodis often used to determine the masses of stars.The mass of a star largely determines manyof the other properties of a star, which is whyastrophysicists need a method for measuringthe mass.