ISP 205 Study Guide - Midterm Guide: Apparent Retrograde Motion, Hard To Explain, Universal Law

Which, if any, of the following statements is/are true?

1)Our galaxy, The Milky Way, is a member of The Local Group, whichis one of several groups of galaxies located in the VirgoSupercluster.
2)Most astrophysicists believe that our Solar System formed from animmense cloud of gas and dust about 4-1/2 million years ago.
3)Planets are believed to have formed by a process known asaccretion.
4)Two key elements in the Condensation Theory of PlanetaryFormation are 5)Conservation of Angular Momentum and CondensationNuclei.
6)The name of the second largest object in the Universe is TheSouthern Wall.
7)In our Solar System, the four jovian planets, Jupiter, Saturn,Uranus, and Neptune, are separated from the four terrestrialplanets, Mercury, Venus, Earth, and Mars, by the Kuiper Belt.
8)Our star, The Sun, is located on the Orion Arm, about 26,000light-years from the center of the Andromeda Galaxy.
9)It takes a photon of light about 4-1/5 years to travel from ourSolar System to the second closest star to Earth, ProximaCentauri.
10)The full range of human knowledge about our Universe spans about40 or 41 orders of magnitude on a spatial scale and about 13.7billion years on a temporal scale.
11)It takes a photon of light about 5-1/2 hours to travel from theSun to the orbit of the former planet Pluto.

Astronomers have observed a small, massive object at the centerof our Milky Way galaxy. A ring of material orbits this massiveobject; the ring has a diameter of about 15 light years and anorbital speed of about 200 km/s.
A) Determine the mass of the massive object at the center of theMilky Way galaxy.
Take the distance of one light year to be 9.461×10¹⁵m. Iwas able to get this it is 4.26×10³⁷kg.
B) Express your answer in solar masses instead of kilograms, whereone solar mass is equal to the mass of the sun, which is1.99×10³⁰. I got this to it is 2.14×10⁷ solarmasses
C)Observations of stars, as well as theories of the structure ofstars, suggest that it is impossible for a single star to have amass of more than about 50 solar masses. Can this massive object bea single, ordinary star? I got this it is no.
D) Many astronomers believe that the massive object at the centerof the Milky Way galaxy is a black hole. If so, what is itsSchwarzschild radius? Express your answer in meters.
E)Would a black hole of this size fit inside the earth's orbitaround the sun? The mean distance from the sun to the earth is1.5×10^11m.
Please solve part D and E. For part D please show equations andsolve all the way through. I worked it twice and I am getting myanswer wrong. I am afraid I am making a silly mistake.