Please i need help answering these questions, a clear answer will be appreciated, i need it within an hour, Thanks

1) If we are using 100 units of labor and 100 units of capital to produce 2500 units of output and we double our labor and capital to 200 each and output increases to 5000, what kind of returns to scale do we have?Why?Will the LAC for this firm be upward sloping, downward sloping or a horizontal straight line?

2)

Refer to the figure below. The profit-maximizing monopoly price is: MC ATC 2 D MR O $2. O $4. O $5. approximately $4.50. Cannot be determined from the information given