Prepare 500 ml of a 1:5 solution using a 1:10 solution and a 1:4 solution. What quantities will be used of each stock solution to make the 1:5 solution?

If you diluted 145 ml of 9% benzocaine lotion to 6%, how much could you produce?

Physician order: NS 500 ml to be administered at 15 gtts/min. The drop factor is 20 gtts/ml. What is the total infusion time for the ordered fluids?

And explain how to get the answers plz