Answer:71 dB
Explanation:
Given
sound Level 
distance 
From sound Intensity





we know Intensity 




Sound level corresponding to 



Answer:
Explanation:
An isentropic process is one that does not change the entropy of the system. A reversible of the universe, and it is reversible because of that. Real processes increase the entropy of the universe, so trying to reverse them would decrease the entropy of the universe, which is impossible, so they are irreversible.
The Carnot cycle has 4 phases:
-Isotermal expansion of gas. In this process it takes heat from a hot source. It is a reversible process, but not isentropic.
-Adiabatic expansion. This one is isentropic, the entropy of the gas remains constant and it doesn't interact with the surroundings. The gas expands not by its own, but the machine makes it expand (it pulls on the gas). The gas cools down.
-Isotermal compression. Reversible but not adiabatic. The gas exchanges heat with the cold source, reducing its volume.
-Adiabatic compression. Adiabatic and isentropic. The machine compresses the gas, causing it to heat up.
Secondary succession, the more common type of succession, occurs on a surface where an ecosystem has previously existed. It occurs in ecosystems that have been disturbed or disrupted by humans, animals, or by natural processes such as storms, floods, earthquakes, and volcanoes.
The image is virtual and smaller than the object is a
description of an image that can be produced by a concave lens.
To add, concave lenses<span> are thinner at the middle. Rays of light that pass
through the lens are spread
out (they diverge). It is a type of diverging lens.</span>