In 2008 the united states, as well as the rest of the world, felt the effects of the recession. after the collapse of the housing market, people lost their jobs and they quit spending money. many people could not afford their mortgages anymore and their homes went into foreclosure. for these people, it was a time of
1) social stratification
2) social inconsistency
3) upward mobility
4) downward mobility

4) downward mobility

Explanation:

Social mobility is the movement of the citizens, individuals, families, or the groups through the system of the social stratification or hierarchy.

If the movement involves the loss in the social class and the economy, it is known as downward mobility.

Thus, in the given case study in which the people after the recession, lost their jobs, house and many other circumstance, shows that it was a time of downward mobility for these people.

b.letter b

explanation:

b) the planets year length would be longer

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