Thanks for the questions! Let's briefly take a look at each stem:
: This question wants to know how many of the soft drinks are "fixed in place" based on the initial rules. So, if a soft drink is always last, for example, that would count as "one." If another soft drink was always third, that would add another, and so on. As it turns out, only M is fixed in place (only N or M could be last from the diagram, but the fourth rule then precludes N from being last, forcing M to be last), and so the correct answer is 1.
: There's a discussion of this question over at: viewtopic.php?f=431&t=11010
that you might find helpful. The basis of the question is to ask how many different soft drinks could be among the top 3. So, we need to look at the various solutions to the game. One solution to the game starts out as L-J-P, and so each of L, J, and P could be in the top 3, and we know at least 3 variables could be in it. Then, another solution starts out with L-P-N, and that adds N, a fourth variable to the mix. Are there any other solutions that start with any other variables besides L, J, P, and N? No, and so the correct answer is 4.
: This is the same question as #10, except a condition is added to the mix that P — J. Under that scenario, M is still last (as always) but L must be first, and P must be second. Thus, the correct answer is 3.
Please let me know if that helps!