Answer:
True
Explanation:
In phase-contrast objective and a phase contrast optical systems is equipped with Light microscope .
Phase contrast microscope is used to differentiate unstained structures in a cell that differ in refractive indices and thickness. Thus it is usefull for examining living unstained organisms.
Light that passed through materials of different refractive index and/or thickness will undergo a change in Phase. The difference in phase or wave front irregularities cause variation in brightness of the structures.
Hoping this might help!!!
I would say D...just because of the greenhouse effect
It is most affected in the surface zone.
The answer would be between b and d but i would go with d
