Answer: I would be able to tell if I was looking at a eukaryotic cell because you would see the cell structures, the specific functions it uses and you would be able to see the nucleus.(both prokaryotic and eukaryotic have cell membranes so this wouldn't really help much in determining).
ATP stands for adenosine triphosphate, where three phosphoric acids attach themselves to provide high energy phosphate groups to it. This process of conversion of ADP to ATP is called as phosphorylation.