Trick question: you just stated everything in the beakers.
Number 13 is D. Mendeleev. He was a Russian chemist and inventor who formulated the periodic table.
Answer:
Try this link https://chem.libretexts.org/Courses/Mount_Aloysius_College/CHEM_100%3A_General_Chemistry_(O'Connor)/08%3A_Solids_Liquids_and_Gases/8.E%3A_Solids_Liquids_and_Gases_(Exercises)
Iron radiates energy faster than lead. Iron has higher heat conductivity than lead.
Answer : The volume range in milliliters for the solution is 0.25 - 0.5 mL
Explanation :
We have been given that there are approximately 20 drops per milliliter of water
This information can be used as a conversion factor as 
We are using 5-10 drops of the solution.
Let us calculate milliliters in 5 drops.

Similarly, 10 drops would contain
solution.
Therefore the volume range in milliliters for the solution is 0.25 - 0.5 mL