Section: Volume K
Explanation/Reference:
Accounts and Users can be associated with multiple opportunities but Opportunities can only be in one territory.

Explanation
Picklist values, help text, and decimal places are three aspects of standard fields that an administrator can customize to suit their business needs. Picklist values are the options that users can choose from a picklist field; they can be added, edited, or deleted by administrators. Help text is the text that appears when users hover over a field; it can be customized by administrators to provide additional information or guidance for users. Decimal places are the number of digits that appear after the decimal point in a number or currency field; they can be changed by administrators to adjust the precision of the field values. Field history tracking and field name are not aspects of standard fields that can be customized; they are only available for custom fields. References: https://help.salesforce.com/s/articleView?id=sf.customize_picklists.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.customize_fields_edit.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.customize_fields_number.htm&type=5

To free up user licenses for new users, the administrator should deactivate the former employees user record.
This will prevent them from logging in and using Salesforce resources, but preserve their historical activities and data. Deleting or freezing user records will not release user licenses. References:
https://help.salesforce.com/s/articleView?id=sf.admin_usermgmt_licensing.htm&type=5