The image contains a mathematical problem related to a three-dimensional geometry, involving a container in the shape of a rectangular prism. The problem describes a water container and asks for the volume of water in the container.

Here’s the breakdown of the problem:

• Container type: The shape is a rectangular prism (box).
• Dimensions: Various distances from points on the container (A, B, C, D) to a horizontal plane (plane $a$) are given.
• Water levels: The water reaches up to certain levels and distances are provided for various points in the box.
• Objective: The question asks to determine the volume of water in the container when the water level reaches a specified height.

To solve this, we need to work with the geometry and measurements provided.

Would you like me to provide detailed steps on solving this, including calculations for the volume of water in this container? Feel free to let me know if you'd like me to break it down further.