Convergence Tests: Help Setting Up Problem & Deriving Limit

[Badgerspin]

Generally when I post, it's with a specific problem. However in this case, the issue I'm running into is that I don't even have the slightest idea of how to even setup the problem to attempt it.

Honestly, I can't seem to find this anywhere in my book and I'm not sure what's really being asked of me. Perhaps it's something simple, but I'm not even sure where to start.

Here's a screencap of what I'm being asked to do.
http://i8.photobucket.com/albums/a3/Bivouac/Picture3-2.png?t=1292024780

I'm not looking for solutions (though I won't complain if one comes around), but I would just like to know what's being asked of me, and how to I setup for this kind of problem.

Any help is appreciated.EDIT: I figured it out. Via the comparison test, everything works out. My only issue now is with the last problem in the set. So any help on that one would be very much appreciated.

Via the comparison test, I derived the two highest powers as the limit approached infinity. This came out to be:

(5^(0.6))/(15^6), however it says that I'm wrong in doing this. Perhaps I'm missing something or made a mistake somewhere in the problem.

 

[Badgerspin]

Disregard. I solved it.

If anyone saw this and was curious about it, here are the answers.
http://i8.photobucket.com/albums/a3/Bivouac/Picture5.png?t=1292032194