You are approached by a mall owner who has outlets selling clothes, sports goods, medications, cosmetics$,$ and stationary. He has branches in various prime locations in your city. The owner has decided to upgrade his current data base system which stores all the data in a single table. You are responsible for identifying the various tables required by the chain of malls. In this regard, help him to upgrade his database by doing the following tasks.

a$.$Identify the different tables with their respective attributes and represent it as an E$-$R diagram. $2$ marks

b$.$Write create statements to create the required tables. $2$ marks

c$.$ Write query to get the average number of the product sold from his various branches from the sales data. $2$ marks

d$.$Write the relational algebra expression for the SQL query. $2$ marks

e$.$Draw the Query tree for the relational algebra expression and calculate the cost assuming the number of tuples in each table. $2$ marks