Draw ER diagram and write relational data models for the following businesses. This lab is based on 1:1 and recursive modeling.

1. A dairy farmer, has several herds of cows. He has assigned each cow to a particular herd. In each herd, the farmer has one cow that is the leader of the herd.

2. Design a database to store product details for a manufacture plant. Some products are purchased from suppliers. A supplier can provide many products; a product, if it needs a supplier, can be only purchased from one supplier. A product can appear as part of many other products and can be made up of many products. The following information of each product should be recorded: product SN (Serial Number), product name, year of build.

3. The originator of a pyramid marketing scheme has a system for selling ethnic jewelry. The pyramid has three levels--gold, silver, and bronze. New associates join the pyramid at the bronze level. They contribute certain percent of the revenue of their sales of jewelry to the silver chief in charge of their clan. In turn, silver chiefs contribute certain percent of what they receive from bronze associates to the gold master in command of their tribe. Finally, gold masters pass on certain percent of what they receive to the originator of the scheme.