Wow, I do not know about feet, but Franmar would. They have a toll free number to call on their site. Get the emerge as well. They are good products.
What I will remind you of, is that it did not work as fast on my den where there had been glued down carpet. Apparently that black mastic was different and it had to sit a lot longer and was not as easy to get up.
But all the mastic under the tile turned to liquid in a couple of hours. If you begin to remove and see it is not all liquid, think about leaving it longer. It will eventually remove.
I purchased 5 gallons and did 3 small bedrooms, closets, a full and half bath and a dining/kit area, and have a little left I am working on my den with and may have to get a little more, but will if needed.