請教一下 勞動供需的題目一題 - 經濟

Consider a straw hat market consisting of 100 identical firms.
There is an unlimited supply of straws and hence straws are free.
The only cost incurred by each firm in production is the wage paid
to workers. The production function of each firm is given by
Q(L)=120L-(1/2)L^2, where Q is the number of hats produced and L is the
number of workers hired.


Suppose that each firm is a price taker in the product market and the
price of a hat is $10, what is the market demand for labor?
(MP(L)= 120-L given the production function.)


可以請教一下這題要怎麼推嗎?麻煩大家了謝謝!

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