A billion solar mass black hole has a radius of only ..

Question

a. 20 A.U.

b. 15 pc

c. 150 km

d. 3 pc

e. 150,000 A.U

Answer 1

Here you go, look it up yourself:http://en.wikipedia.org/wiki/Supermassiv...

Answer 2

Here's a clue.  If the mass of the entire universe were put into a black hole, the S. radius would be less than that of the solar system.

If this is a physics question, assume the entire mass is a point, then calculate at what distance from that point the escape velocity would be equal to c.