How can Approver able to check the history of their delegated approval requests

Invoice Approval Workflow

If approver A (delegator) has setup the vacation rule and all the approval request will delegate to user B (delegatee)

When approver A's vacation rule ended (return from holiday), how can approver A able to check how many approval requests are sent to her and the responds from the delegatee user B 

Eg. When B reply the approval request and 

Did B rejected or approved the approval and 

What's B's comment in the respond etc.