As defined in the Act, the term ``enterprise'' is roughly
descriptive of a business rather than of an establishment or of an
employer although on occasion the three may coincide. The enterprise,
however, is not necessarily coextensive with the entire business
activities of an employer. The enterprise may consist of a single
establishment which may be operated by one or more employers; or it may
be composed of a number of establishments which may be operated by one
or more employers. On the other hand, a single employer may operate more
than one enterprise. The Act treats as separate enterprises different
businesses which are unrelated to each other and lack any common
business purpose, even if they are operated by the same employer.