Field of view

The amount of physical space covered by an image is its field of view, which is calculated from two properties:

• Array shape, the number of data elements on each axis. Can be accessed with the shape attribute.
• Sampling resolution, the amount of physical space covered by each pixel. Sometimes available in metadata (e.g., meta['sampling']).

For this exercise, multiply the array shape and sampling resolution along each axis to calculate the field of view of vol. All values are in millimeters.