In which case would a scientist choose to use a dissecting microscope rather than a compound

Compound microscopes are capable of greater magnification and resolution, but need to be used with very small objects that the light can easily pass through. Dissecting microscopes are used for examining larger, thicker objects at lower magnification.

Explanation:

The dissecting microscope is configured to allow low magnification of three-dimensional objects- objects larger or thicker than the compound microscope can accommodate. Furthermore, the two separate lenses of the binocular dissecting microscope allow one to see objects in three dimensions, i.e., in stereo.

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