Answer:
The natural medium emanating from the Sun and other very hot sources (now recognised as electromagnetic radiation with a wavelength of 400-750 nm), within which vision is possible.
Explanation:
just the way it is
Here refrigerator removes 55 kcal heat from freezer
Refrigerator releases 73.5 kcal heat to surrounding
So here we can use energy conservation principle by II Law of thermodynamics
the law says that

here we know that
= heat released to the surrounding
= heat absorbed from freezer
W = work done by the compressor
now using above equation we can write



So here compressor has to do 18.5 k cal work on it
Answer: a
Explanation: because i said so
<span>Newton's law of universal gravitation is an INVERSE SQUARE LAW, which rules out C and D.It is proportional to the masses involved, which rules out B.A could be seen as one form of the lawF=G m1 m1/r^2Though I recognise it more as F=G m1 m2/r^2.G is the universal gravity constant and is distinct from g which is the acceleration of gravity LOCAL to a planet or moon. So, g is LOCAL, G is universal.Newton was a smart bloke, as are all these scientists whose names frequently appear.
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