17.48: In the binary star system shown, the two star
l8e*pxibp r5/ s follow circular orbits about the system’s center of mass. The s
x8ie lpp */5rbtars are separated by a distance D that is large compared to their size and are subject only to their mutual gravitational attraction. The orbital period of the star of mass M is T. Which one of the following choices represents the total mass of the binary star system?