Who consumed the most water based on the following amounts: Don: 1 liter, Sam: 1 gallon, Maria: 1 milliliter, Jenny: 1 quart?

To determine who consumed the most water, we need to compare the volumes measured in different units: liters, gallons, milliliters, and quarts.

1. Don consumed 1 liter. The liter is a common metric unit for volume.

2. Sam consumed 1 gallon. In metric terms, 1 gallon is equivalent to approximately 3.785 liters, which is significantly more than Don's 1 liter.

3. Maria consumed 1 milliliter, which is a much smaller volume, as there are 1,000 milliliters in a liter. This means Maria's amount is substantially less than Don's 1 liter.

4. Jenny consumed 1 quart. A quart is approximately 0.946 liters. This is also less than what Don consumed, as 1 liter is greater than 1 quart.

When we compare all the amounts converted to the same unit, Sam's consumption of 1 gallon (about 3.785 liters) is clearly more than Don's 1 liter, Jenny's 1 quart, or Maria's 1 milliliter. Therefore, Sam consumed the most water.