How many gallons of water does a 10 x 10 x 14 sink hold?

10 x 10 x 14= 1400= volume of the sink

without any units for these measurements it is not possible to determine how many gallons of water the sink can hold.

However assuming that the lengths were given in centimeters we find that the volume is 1400cm3 or 1400 ml which is equal to 1.4 liters. now one must convert liters to gallons. 1 gallon is approximately 3.785liters.

so (1.4 liters) x (1gallon/3.785liters) is approximately 0.3699 gallons