Order these objects by size (radius) from smallest to largest:
A) 3 solar mass black hole, 3 solar mass neutron star, 0.5 solar mass white dwarf, 1 solar mass white dwarf.
B) 0.5 solar mass white dwarf, 1 solar mass white dwarf, a 3 solar mass neutron star, a 3 solar mass black hole.
C) 3 solar mass neutron star, 3 solar mass black hole, 1 solar mass white dwarf, 0.5 solar mass white dwarf.
D) 3 solar mass black hole, 3 solar mass neutron star, 1 solar mass white dwarf, 0.5 solar mass white dwarf.
E) 0.5 solar mass white dwarf, 1 solar mass white dwarf, a 3 solar mass black hole, a 3 solar mass neutron star.
F) 1 solar-mass white dwarf, 0.5 solar-mass white dwarf, a 3 solar-mass neutron star, a 3 solar-mass black hole.
Question 2
During the time that a planet is in its period of apparent retrograde motion, ________.
A) the planet is getting closer to the Sun in its orbit
B) the planet appears to rise in the west and set in the east, rather than the usual rising in the east and setting in the west
C) over many days or weeks, the planet moves westward relative to the stars, rather than the usual eastward relative to the stars
D) the planet moves backwards (clockwise as viewed from above Earth's north pole) in its orbit of the Sun
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