Longer Phones, Email and an Active Flag

The task runs on a small copy of the Customer table: CustomerID, FirstName, LastName and Phone (nvarchar(15), optional), 3 customers. Change the table without recreating it:
- international numbers don't fit: make Phone up to 25 characters, still optional;
- add an optional column EmailAddress, Unicode text up to 50 characters;
- add a required column IsActive of type bit with the default value 1, so that the existing customers become active.