What is the major observational difference between a Seyfert galaxy and a normal spiral galaxy?
a. Normal spiral galaxies usually have shorter spiral arms.
b. Normal spiral galaxies never contain a supermassive black hole at their center.
c. The central region of a Seyfert galaxy is much brighter.
d. Seyfert galaxies don't contain any star formation.
c
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Consider an electron in a hydrogen atom. How does the wavelength ? of an energy eigen function (as measured around the circular band) depend on the energy E associated with that eigen function?
A. ? ? ?E?
B. ? ?
C. ? is independent of E.
D. ? ? 
E. ? ? 1/?E?
A rock is projected from the edge of the top of a building with an initial velocity of 12.2 m/s at an angle of 53° above the horizontal. The rock strikes the ground a horizontal distance of 25 m from the base of the building. Assume that the ground is level and that the side of the building is vertical. How tall is the building?
A. 25.3 m B. 29.6 m C. 27.4 m D. 23.6 m E. 18.9 m
How many nonbonding pairs of electrons are in the following molecule?
H—H A) 1 pair B) 6 pairs C) 0 pairs D) 8 pairs E) none of the above
The velocity of sound in sea water is 1.53 × 10^3 m/s. Find the bulk modulus (in N/m2) of sea water if its density is 1.03 × 10^3 kg/m3
a. 2.57 × 10^9 b. 2.19 × 10^9 c. 2.04 × 10^9 d. 2.41 × 10^9 e. 2.82 × 10^9