1.) people that benefit from social stratification are those that have many opportunities, are more wealthy, and have been more socialized in society. Those who don't are the poorer. The gap between rich and poor in America is very large and still growing. In my opinion, the poor don't have as many opportunities as the more wealthy classes.
2.) I believe my every individual in my family and others all experience upward mobility. We start off with a small job and as we get more experience and skill we get better ones. Also, I think we have experienced intergenerational mobility. The society has evolved and so has standards and jobs that push us to be better. I don't believe we have intergenerational mobility because everyone starts off lower on the ladder and move to where there skill level is, most likely.
3.) Keeping up with the Kardashians is an example of high class ranking. They are celebrities so people follow their trends and their lives. The Kardashian/Jenner family has a lot of power through influence. They obviously have money too.