Q1. Who are the two types of users that can grant sharing privileges on a given record?
To grant access to a record, you must be one of the following users. - The record owner - A user in a role above the owner in the hierarchy (if your organization’s sharing settings control access through hierarchies) - Any user granted “Full Access” to the record - An administrator
Granting Access to Records https://help.salesforce.com/articleView?id=granting_access_to_records.htm&type=0
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