Draw a standard ERD for the following problem, indicating each field, the primary key and any foreign keys for each table. Be sure to show the relationships and the cardinalities.

A computer has one and only one Image. An Image can be loaded on many computers. An Image consists of several software programs. Many software programs make up an image. A computer is assigned to only one person but a person can have more than one computer assigned to her. The person is assigned to only one business unit which is made up of many people. Each business unit has only one site but a site may contain many business units.