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which are characteristics of natural selection? check all that apply.
it affects populations.
it affects only individuals.
it occurs when there is genetic variation
it occurs when organisms are genetically identical.
it selects organisms with certain traits to survive.
it selects organisms at random to survive.

Characteristics of natural selection are

Explanation:

The theory of natural selection was the brainchild of Charles Darwin who discredited all the previous theories of random selection. According to him, it is a mechanism whereby the fittest are chosen to reproduce their like and pass on their genes.

The individuals of a population that have characteristics that are more suited to the harsh and dominant environment will more likely survive and later pass on their advantageable genes to their offsprings while those who cannot adapt will perish. As this process continues to occur, the entire species will evolve in time.

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.

explanation: