Which of the following is not a model of the solar system? a. heliocentric model c. nebula model b. geocentric model d. all of the above are solar system models

c. Nebula model

Explanation:

Solar Nebula hypothesis describes that the solar system - the sun and all planets were formed from the solar nebula about 4.5 billion years ago. Thus, it is not a model of solar system.

Heliocentric model and geocentric model describe how Earth, sun and other planets revolve.

Heliocentric model suggests that Sun is at the center and all the planets along with earth revolve about it where as geocentric model suggests the Earth at the center of the solar system with sun and other planets revolving about it.

Thus, the correct answer is c.

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.