At least how many standard solutions would you need to make a calibration graph, assuming that the graph is expected to be a straight line? Explain your answer. Don't include the data from distilled water in this question.
Not much to go on here. I assume the question relates to the minimum number of solutions you need for a straight line graph. If we know it is a straight line we need at least two points. If we know that the line goes through zero then we need only one solution.
