Request for Information and Pre-Qualification Questionnaire can be used for short-listing suppliers. Request for Quotation is used when the only variable is price and you would like suppliers to submit a price for you.
Invitation to Tender would be the next stage after RFI / PPQ- this is sent out to those suppliers who have passed selection, and details the second stage of the competition. See p.75 for more details.

The Kraljic model "plays a key part in category management" p.19 of the textbook. Category Management = the spend in an organisation, broken down into categories of related products (e.g. IT, facilities management, marketing). Each of these categories could be plotted on the Kraljic Matrix.

Comprehensive and Detailed Explanation:
In Michael Porter's Value Chain model, primary activities are those that are directly involved in the creation and delivery of a product or service. These include:
* Inbound Logistics:Activities related to receiving, storing, and distributing inputs internally.
* Operations:Transforming inputs into the final product.
* Outbound Logistics:Distributing the final product to customers.
* Marketing and Sales:Activities that inform buyers about products and services, induce buyers to purchase them, and facilitate their purchase.
* Service:Activities that maintain and enhance the product's value, such as customer support and repair services.
Firm infrastructure and technology development are considered support activities, as they assist the primary activities in helping the organization achieve its competitive advantage.
Reference:
CIPS L4M6 Study Guide

Routine suppliers typically supply low-value, low-risk items. Maintaining partnerships in such cases is inefficient since alternative suppliers are readily available. Adopting a transactional or adversarial relationship would be more appropriate.

A product with an 'inelastic price' means that consumption doesn't really depend on how much it costs. So you could increase the price of alcohol and cigarettes and people would tend to still buy them. A product with an elastic price means that a change in price would have a large affect on the number of people who bought the item. See p.95 for more details on price elasticity.