How to Open SharePoint Excel document URL in SharePoint viewer from external document URL reference?

I've been researching and trying this but I wanted to know if the following is possible...

I was presented with a request from a customer using SharePoint asking if they could open an Excel document located on SharePoint via the URL path in an external document,but there were two add'l requirements:

1. they would like the Excel document to open within SharePoint's viewer vs. the Office application.  (e.g. xlsx opens in SharePoint vs MS Excel Office instance)
2. They would like it to open to a specific Worksheet tab.

Requirement 1 I'm at a total loss.

Requirement 2 I have done some researching and a recommendation to opening to a specific tab (Worksheet) stated I need to include ?web=1?range=Sheetname but haven't been able to get it to work. 

e.g. https://mycompany.com/sites/mySP/Shared%20Documents/Docs%20and%20/myExcel.xlsx?web=1?range=Sheetname

Any thoughts, suggestions, or links that might be useful?

Thanks

SV