Marginal Product is: The marginal product of any input is the increase in total output obtained from a one unit increased in the output.
Marginal Cost is: The increase in output that arises from and additional unit of input.
Average Product is: Equal to the total product divided by the quantity of labor employed, usually abbreviated(AP), is found by dividing total product by the quantity of the variable input. Formula: Average Product = Total Product/Variable Inputs
Average Cost is: Cost of producing a single unit of product at a particular output. Formula: Average Cost = Total Cost/Output.
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