This organelle is found in plant cells. the function of this organelle is to collect solar energy and use this to produce food, or glucose, for the plant. this organelle is the

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link:

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.