Consider a distillery that produces whisky. The main physical limitation on how much whisky can be made by the distillery is the number of stills in operation (the still is the piece of equipment that actually does the distilling). Suppose the distillery can produce the following amount of whisky depending on how many stills it uses:

Number of stills used	Barrels of whisky per week
0	0
2	3.0
4	6.0
6	8.0
8	9.0

Calculate the marginal product for each still (give your answer to one decimal): first still: barrel(s) fourth still: barrel(s) sixth still: barrel(s) eighth still: barrel(s)

How do I calculate marginal product for the first barrel?