The length and width of the park are measured in linear units: inches, miles, meters, etc. The area is measured in square units. Explain the reason for using square units for area of the park.

Square units are used to measure the are of the park because it is the international metric unit that is used to measure areas of big chunks of land or topographical areas. If inches, miles, and meters are to be collectively used, it would not create the idea that the area being measure is large.