An unlabeled bottle of clear liquid is found on a shelf. A sign on the shelf says, "Tris-EDTA Buffer, pH 8.0." What is the proper course of action? 1) Use the liquid as Tris-EDTA. 2) Taste the liquid to make sure it isn't saline. 3) Dispose of the liquid. 4) Measure the pH. If it is 8.0, proceed to use the liquid as Tris-EDTA.