The reasons why a language would distinguish between uppercase and lowercase in its identifiers are:
(1) So that variable identifiers may look different than identifiers that are names for constants, such as the convention of using uppercase for constant names and using lowercase for variable names in C.
(2) So that the catenated words such as names can have their first letter distinguished, as in Total Words. The primary reason why a language would not distinguish between uppercase and lowercase in identifiers is it makes programs less readable, because words that look very similar are actually completely different, such as SUM and Sum.
Critical path method (CPM) is a step-by-step process by which critical and non-critical tasks are defined so that time-frame problems and process bottlenecks are prevented.
please see attachment for the step by step solution of the given problem.
