The ________ Excel function category works with URL and XML connections

A__________ is data appended to, or a cryptographic transformation of, a data unit that allows a recipient of the data unit to prove the source and integrity of the data unit and protect against forgery.

Fill in the blank(s) with the appropriate word(s).

____________________ a layer is a good way to preserve modifications to a layer because you don't have to worry about losing your original work.

Fill in the blank(s) with the appropriate word(s).