Explanation
The object that is required to create a Sales agreement is Contract. A Contract is a document that outlines the terms and conditions of a sales agreement between two parties. It is necessary to create a Contract in order to create a Sales agreement. For more information, please refer to the Salesforce documentation.

Explanation
To conduct proper testing of Manufacturing Cloud, the end users need the following items:
Sandbox access: A sandbox is a copy of the production environment that allows users to test changes and features without affecting the live data. Manufacturing Cloud offers different types of sandboxes for different testing purposes, such as learning, pre-release, and base12.
Test data: Test data is a set of realistic and representative data that is used to simulate the actual business scenarios and workflows in Manufacturing Cloud. Test data can be created manually, imported from external sources, or copied from the production environment34.
Process scripts: Process scripts are step-by-step instructions that guide the users through the testing scenarios and expected outcomes. Process scripts help to ensure that the testing is consistent, comprehensive, and aligned with the business requirements . References: Create a Manufacturing Cloud Trial Org, Try Manufacturing Cloud for Free, Create Test Data for Your Full Sandbox, Import Data into Your Org, [Create a Test Plan for Your Salesforce Implementation], [Test Your Salesforce Implementation].

Explanation
Sales Agreements is a feature that allows businesses to set up automated agreements between themselves and their customers. Account Based Forecasts allows businesses to forecast their run-rate and net-new business by analyzing historical data and trends. Both of these features are available in the standard Manufacturing Experience Cloud Template.

: A System Integration Testing (SIT) environment is used as an environment to perform system-to-system testing.
This means that the SIT environment is used to test the integration of different systems or components that are part of the Salesforce Manufacturing Cloud solution. The SIT environment allows the verification of the functionality, performance, and reliability of the integrated systems, as well as the identification and resolution of any defects or issues that may arise during the integration process. The SIT environment is typically a replica of the production environment, but with a smaller data set and lower security requirements. The SIT environment is also used to validate the data migration and synchronization between the source and target systems, as well as the compatibility and interoperability of the APIs and web services that are used for the integration. Reference:
Manufacturing Cloud - Salesforce
How to Perform Automated Integration Testing in Salesforce
Automate and Test During Integration

The Time Period filter on a sales agreement record page allows you to view the sales agreement terms and schedules for different time periods. You can choose from three options: Range, Set Periods, and Current Period. Range lets you specify a start and end date for the filter. Set Periods lets you select up to eight periods from a list of predefined periods, such as quarters, months, or weeks. Current Period shows the current period based on the sales agreement's period type and start date. Custom and Fiscal Year are not available options for the Time Period filter. Reference: = Filter Sales Agreement Schedules by Time Period, Filter Sales Agreement Terms by Products or Categories