Is the conclusion true or false?

Question

Given the premises, the conclusion of each argument that
follows is it (a) true beyond a reasonable doubt, (b) probably true, or (c) possibly true or possibly false.
5. Since the graduates of Harvard, Yale, Princeton, and other Ivy League schools generally score higher on the Graduate Record Examination than students from Central State, it follows that the Ivy League schools do more toward educating their students than Central State does.
6. Michael Jackson has had more plastic surgery than anybody else in California. You can bet he’s had more than anybody in Connecticut!
7. When liquor was banned in 1920, hospitalizations for alcoholism and related diseases plummeted; in 1933, when Prohibition was repealed, alcohol-related illnesses rose sharply again. Legalization of cocaine, heroin, and marijuana would not curb abuse of those substances.

Answer 1

5. C - There are many possible other explanations, even given the premise.
6. B - If MJ has had more than anyone in California, he has probably had more than anyone in Conneticut.
7. B - It is hard to extrapoloate beyond a reasonable doubt from just one instance.

Answer 2

5 We know that students at Ivy League colleges have higher entrance requirements and come from richer families than other students. Given that, then the teachers are probably the best qualified and paid more than other teachers so I would go for (b) since you cannot guarantee that students there get any other benefits than they do at State Uni.

6 On the assumption that Michael Jackson actually HAS had the most plastic surgery in California it doesn't follow that everyone in Connecticut has had less. For example if No-one at all had plastic surgery in California (Far fetched I know) except for him having, say an eyebrow tuck and EVERYONE in Connecticut had at least two ops then it wouldn't be true so it's got to be (c)

7 Although the correlation between alcohol intake and related illnesses is fact it does not follow that legalising drugs would either increase or reduce abuse. On the assumption that legal control would have an increased improvement on users abuse could be curbed but it depends how you define abuse. If you mean 'over indulgence' then that would probably reduce since legalisation would take away the 'dare' factor with less younger people trying. I would say (c).

Answer 3

5. c-Ivy League schools have higher admittance qualifications than most colleges, so it could be that, but we don't know for sure do we?
6. c-It is possible that SOMEONE in Connecticut has had more than Michael, but we don't know for sure do we?
7. c-Maybe, maybe not, we don't know for sure do we?

Answer 4

5. = C
6. = A
7. = A