Consider a monopolistically competitive market with N firms. Each firm's cost and demand are described by the following equations:
Demand: Q=600/N - P
Marginal revenue: MR=600/N-2Q
Total Cost: TC=75+2Q^2
Marginal Cost: MC=4Q

What will be the number of firms in long run equilibrium? (Hints: Calculate the average total cost equation firstly)

不懂怎樣計算啊, 怎樣計也是小數來的。
跪求各位達人出手相助
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