Workbook sharing and Password protection

[Deleted]

I want to share excel workbook with 20 different people but I want that they can only view and work on the particular sheet assigned to them and they have no visibility to another sheet, only admin have all the rights in the workbook, and each sheet should have there unique passwords. 

[#2]

Hi,
you can create different ranges with different passwords, so a user can only edit a range if he knows the specific password for this range. To do this, goto menu "Review | Allow Edit Ranges". Then create as many new ranges as you need and set the individual passwords for these ranges.

But there is no standard functionality in Excel to view specific worksheets only to specific users.