Consider the very schematic rotation curve of the Galaxy shown in the figure. Using this rotation curve and assuming that the Sun is 8 kpc from the Galactic center, determine (A) the mass of the Galaxy interior to the orbit of the Sun in units M and (B) the rotation period of the Sun around the Galactic center in units yr. Then (C) show that a mass density profile (R) / R2 produces a flat rotation curve, consistent with the shape of the rotation curve shown in the figure