<span>All the options (heat, pressure, deposition and chemical environment) are correct.<span>
Metamorphic rocks are formed when pre-existing rocks are subjected to heat, pressure and hot mineral rich fluids which cause physical, chemical and mineralogical changes to the rock. Metamorphic rocks are grouped by chemical, texture and mineralogy. The common metamorphic rocks include schist, marble, and gneiss.
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Answer:
Thus, the minimum number of photons per second is 77.34
Explanation:
Light intensity,
= 
Pupil has a diameter, d = 8.5 mm
= 8.5 x
m
Radius of the eye, r = 4.25 x
m
∴ Area of the eye, A = 
= 
= 
Let
be the minimum number of photons.
Therefore,
=
x A
=
x 
=
W
Thus the minimum number of photons is given by

where E = 
= 
= 
Therefore,
= 
= 77.34 photons per second
Thus, the minimum number of photons per second is 77.34
Answer:
c. Clouds
Explanation:
It is the process called as condensation. Condensation is when the water vapor moves up to from clouds.