Your friend want to know the amont of salt added to her favorite fast food french fries what would you recommend that she do to find out the amount of salt

That nutritional information is usually not posted up on the wall,
but by federal law, it's available on request, to any customer, at
any fast-food place. 

All she has to do is ask to see the manager, and then ask the
manager for the nutritional information booklet. 

She'll get a nice printed booklet that tells the salt content in the
fries, AND the amount of many other substances in ALL the items
sold at that place.

It's the law.  Don't be bashful.