Solution:

Traffic volume is defined as the number of vehicles crossing a section of road per unit time at any selected period.

Traffic capacity is expressed as the maximum number of vehicle in a lane or a road that can pass a given point in unit time, usually an hour

Traffic density is the number of vehicles occupying a given length of the highway in a traffic lane. It is expressed as vehicle/mile or vehicle/kilometer.

Basic capacity is the maximum number of vehicles that can pass a given point on a lane or a roadway during one hour, under the ideal roadway and traffic conditions that can possibly be attained.