The amount of time that a student spent out of the country. continuous or discrete?

the volume of water in a randomly chosen pool. continuous or discrete?

the number of times that the water fountain is used in a week. continuous or discrete?

A continuous variable is a value that can be subdivided on a value between any other two values, such as: indoor temperature, time spent waiting, water consumed, color wavelength, and direction of travel.

1) The amount of time that a student spent out of the country is :CONTINUOUS.
(Time, Length, height, Volume, Area, temperature, color wavelength are all continuous)

2) Volume of water in a randomly chosen pool :CONTINUOUS

3) The number of times that the water fountain is used in a week: DISCRETE