A pharmacy uses 4×10^−3 liter of an active ingredient in one dose of a medication. The active ingredient comes in a 2-liter bottle. How many doses of the medication can be made with one bottle of the active ingredient? Write your answer in standard form.

Since each bottle is made up of 2-liter of the active solution, in order to determine the number of doses of the medication that can be made, we just have to divide 2 L by 4x10^-3.
                  number of doses = (2 L) / (4x10^-3L/dose) = 500 doses
Therefore, the pharmacy can make 500 doses of the medication.