Which of the following things is an “extended object”? For each item, answer “A” if the item is an acceptable extended object, “B” if the definition of an extended object applies badly to the item, and “D” if it is debatable.
(a) An electron
(b) An atom
(c) A rock
(d) A swarm of bees
(e) The earth’s atmosphere
(f) The water in an ocean current
(g) Sugar molecules dissolved in a cup of water
(h) The vacuum between galaxies
(a) An electron -B
(b) An atom - A
(c) A rock - A
(d) A swarm of bees - D
(e) The earth’s atmosphere - A
(f) The water in an ocean current - B
(g) Sugar molecules dissolved in a cup of water - B
(h) The vacuum between galaxies - B
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a. 
b. 
c. 
d. 
e. 0
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