This section is about triple integrals.
Here are some recommended problems:
14.5: 1, 2, 5, 6, 9, 10, 17, 18, 21, 22, 27, 28, 29, 30, 35, 36, 37, 38, 41,
and here is an introductory video and an example:
Example of setting up a triple integral in two ways: