Give an E-R diagram (entities, relationships, and cardinalities) and a minimal relational database for the following business process.
J&B Enterprises offers each of its clients a full range of outsourcing service options which allow those companies to concentrate almost exclusively on their main value-added activities. J&B will do your bookkeeping, computer services, taxes, cleaning, advertising, legal work, etc. for you by dispatching its own well-trained employees to your place of business. Each service engagement involves exactly one type of service, and it must include at least one engagement employee. Each type of service has a standard hourly billing rate. Employees can engage in multiple service engagements, but they have just one hourly wage rate. When a service engagement is completed during a particular month, that client is required to pay in full for it by the 20th of the next month (if a client has had more than one service engagement, one payment can be submitted for all of the engagements). Clients NEVER make partial payments. Although the vast majority of cash receipts come from clients for service engagements, some cash receipts come from other sources (e.g. bank loans). Every cash receipt is processed by exactly one of J&B’s several cashiers and is deposited into one of J&B’s bank accounts. Information about service types, cashiers, engagement employees, and clients will often need to be entered into the database before any transactions involving them have occurred. Information about cash accounts may not be entered into J&B’s system without assigning at least one cash receipt to that account. The following attributes are of interest to potential users of this data model.