Answer:
liquid A will evaporate at 25/18 cups per hour.
liquid B is 8/3 cups per hour.
Explanation:
To calculate the unit rate you need to calculate per hour, remember that unit rate always uses as numerator number 1.

So the liquid A will evaporate at 25/18 cups per hour.
And the liquid B:

So the evaporation rate of liquid B is 8/3 cups per hour.