You have been asked to develop a data model for the Drip Drip Water Company (DDWC). DDWC is the sole supplier of water to the citizens and businesses of the town of Drip Drip.
Each of DDWC’s customers is classified as being either residential or non-residential. Each customer has at least one water meter that measures the water consumed by the customer at a particular address. Water meters must be replaced when they have been in use for 5 years.
All customers are billed monthly. Meter readers, who are employed by DDWC, are paid per meter they read. They are each allocated up to 1000 meters to read each month.
Once the reader has read the meter, the reading is recorded and the bill for that customer is