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Multiple choice: The presence of a black hole in a galaxy core can be inferred from (a) the total mass of the galaxy; (b) the speeds of stars near the core; (c) the color of the galaxy; (d) the distance of the galaxy from the Milky Way Galaxy; or (e) the diminished brightness of starlight in the galaxy core, relative to surrounding areas.

Multiple choice: Which one of the following statements about black holes is false? (a) Inside a black hole, matter is thought to consist primarily of iron, the end point of nuclear fusion in massive stars. (b) Photons escaping from the vicinity of (but not inside) a black hole lose energy, yet still travel at the speed of light. (c) Near the event horizon of a small black hole (mass \(=\) a few solar masses), tidal forces stretch objects apart. (d) A black hole that has reached an equilibrium configuration can be described entirely by its mass, electric charge, and amount of spin ("angular momentum"). (e) A black hole has an "event horizon" from which no light can escape, according to classical (i.e., nonquantum) ideas.

Fill in the blank: Mass causes the surrounding space-time to ___.

Fill in the blank: According to Einstein's general theory of relativity, a black hole is completely described by its ___, ___ and ___.

Fill in the blank: The ___ of a black hole is its boundary, defining the region from within which nothing can escape (ignoring quantum effects).

Fill in the blank: All of the matter that falls into a black hole becomes concentrated in a very small volume called a ___. 'This question requires a numerical solution.