a supersatured sugar solution (can/ cannot) be used in a calibration graph.

What kind of graph, but probably not since you won't know the degree of supersaturation.

A supersaturated sugar solution cannot be used in a calibration graph.

A calibration graph is typically used to determine the relationship between the concentration or amount of a specific analyte in a solution and the response of an analytical instrument or method. This graph is constructed using a series of standard solutions with known concentrations or amounts of the analyte.

In the case of a supersaturated sugar solution, it means that the solution contains more dissolved sugar than is normally possible at a given temperature. While supersaturated solutions can be useful for some specific purposes, they are not suitable for calibration graphs because the degree of supersaturation cannot be accurately determined. The excess sugar precipitates out of the solution, making it difficult to know the exact concentration or amount of the analyte at different points along the graph. Therefore, it is recommended to work with saturated or unsaturated solutions when constructing a calibration graph to ensure accurate and reliable results.