Answer:
The correct answer would be the slide should be almost in focus when changing to higher magnifications.
A parfocal lens is a type of lens which stays in focus when focal length or magnification is changed.
Parfocal microscopes are those in which objectives remain in focus even when magnification is changed for example, when it is switched from 10x to 40x, the object or slide remains at the focus.
The however is True.
The correct answer would be True
If a star is a brilliant blue color, it's really hot and emits a lot of energy. If it's red, it has a cool surface temperature instead. Therefore, the dominant wavelength of a star's light can tell us its surface temperature.
The answer is D
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