Question

This experiment, you compare several unknown powders to known powders. What is the name given to all of the known materials used for comparison in this experiment?

A.quantities
B.controls
C.constants
D.variables

Answer 1

the correct answer is B .Controls

Answer 2

B. Controls: The known powders attributes are already studied, so the are used as control measures to compare with the findings in the experiment with the unknown powders.