Answer :

The expression that shows the total gallons is 0.5gallon/1 day*16cups/1gallon * 7days/1week

Dimensional Analysis

From the given question, we are told that Katrina drinks 0.5 gallons per day. In order to determine the total cup that she drank in a a week, we will have:

Total gallons in a week. = 0.5gallons/1 day * 7days/1

Total gallons in a week = 3.5 gallons

Since 1 gallon. = 16 cups, then;

3.5 gallons = 16cups/1gallon * 3.5gallons

3.5 gallons = 56 cups

Hence the expression that shows the total gallons is 0.5gallon/1 day*16cups/1gallon * 7days/1week

Learn more on dimensional analysis here: https://brainly.com/question/18559676

#SPJ1