請教一些經濟學問題 - 經濟

一 if minimum average cost is the same over a large range of output,

a) the market will evolve into a natural monopoly
b) minimum efficient scale is large as well
c) only a few large firms will survive in the long run
d) smaller firms have a cost advantage over larger firms
e) firms of varying sizes can coexist

答案是b 可是我不太懂整個題目的意思

二 technological changes that decrease minimum efficient scale
a)reduce concentration
b)increase concentration
...

答案是b 我也不太懂它在問什麼...


請問有人可以告訴我嗎

感恩^^

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