Consider Retail Store database which store the details of
different items available in the store and the sales of these items
to different customers: Schema: Item(ItemNo, ItemName, Category,
UnitPrice) Sales(SalesNo, ITemNo, SalesDate, CustomerNo, Qty)
Customer(CustomerNo, CustomerName, City, Income, MobileNo) Write
the following queries in Relational Algebra:
a) List the No. and Name of items in ‘ABC’ category.
b) Count the No. of categories from which the items were bought
by the customer ‘Mohan Kumar’
c) List the customers who has...