Answer:
50
Step-by-step explanation:
According to the question, The computation of the quantity produce is shown below:
Here we use the differentiation LRAC to zero
![(\partial LRATC)/(\partial Q)=-10+0.2Q=0\\\\ 0.2Q=10\\\\ Q=50](https://img.qammunity.org/2021/formulas/business/college/i37w670v6upkis63ikvlaj3qq43uph9pi5.png)
From above calculation it can be concluded that the each firm would be produced the quantity of long run equilibrium for 50
Hence, the first option is correct