Explain the economic concept illustrated by the figures of marginal product (MP) in the table and define 'variable input'.

Here are the solutions to the questions:

Part (a)
The economics concept illustrated by the figures of marginal product (MP) in the table is the Law of Diminishing Marginal Returns.
This concept states that as more units of a variable input (like labor) are added to a fixed input (like machinery or land), the additional output produced by each new unit of the variable input will eventually start to decrease. Initially, adding more workers might increase efficiency, but beyond a certain point, they start getting in each other's way, leading to smaller and smaller increases in total output.

Part (b)

• Variable Input: An input whose quantity can be changed in the short run to alter the level of production. In the given table, the *Variable Input