Relation algebra only please. Cant use PROD.P#, ORDERS.P# or any the same format.

Only need numbers 4-7

See #1-3 for sample answers

CUST This is a table with information about customers of DU Corp. The attributes are: C# Customer # NAME Customer Name CITY City (where the Customer Score (number C SCORE customer is located)between O and 10) 532 John Smith Chicago 6 PROD This is a table with information about the products that the company currently sells. Product #s are unique, but names are not. The attributes are: NUM H UPRICE product) 123.56 True NEW P# Product # NAME Product Name Number on Hand Unit Price (Price of each Boolean field that (Inventory) specifies if the product is new or used 9A2B Desk ORDERS This is a table with information about the orders received by the company. Not all of the customers currently have orders placed. customer can have multiple orders. An order can have multiple products in it, but each product would only appear once. The attributes are: .NUM Customer Number P# Product Number QNTY Quantity Purchased pecial SPECIAL ORDER# Order# 238 532 9A2B Ship Frozen 1. What are the primary keys for these three tables? CUST: C# PROD: P# ORDERS: ORDER# 2. Write a query to get the number and name for all customers that are located in Eigin and have scores under 6. ( CUST where City-Elgin, AND C-SCORES