For the given database users requirements in the following statements or paragraphs, please construct the corresponding E-R diagram (entities and relationships), defined the key for each entity, indicated the participant constraints (total vs. partial, mandatory vs. optional), and indicate the cardinality of each entity involved in a relationship.

a) A supplier supplies certain number parts for a project, a project uses some parts from different suppliers, and the same kind parts from different suppliers are used by different projects. A supplier has a supplier number, supplier name, and the city the supplier locates. Each part has a part number, part name, part color, part weight, and city where the part is manufactured.