Why do astronomers believe supermassive black holes are the source of an AGN's energy?
a. Such black holes have been found at the center of most galaxies, both active and inactive.
b. Radio jets are seen from low-mass black holes plus accretion disks inside our galaxy.
c. Jets and accretion disks have been observed in active galaxies.
d. Black holes can produce so much energy in such a small place.
e. All of the other choices are correct.
Question 2
When material expanding away from a star in a binary system leaves a star's Roche lobe,
a. the material will start to fall back toward the star.
b. all of the material will accrete on to the companion.
c. the material is no longer gravitationally bound to that star.
d. the material will increase in temperature an eventually undergo thermonuclear fusion.
e. c and d.