This is really easier than you think. You're comparing apples and oranges, or even better, peanuts and cashews. If you need a truck, a Jeep will not do. If you're going to haul stuff, anything too tall or long or dirty or rough to fit in the Jeep, at least once a month, you need a truck. If...
It depends on the starting time of your AIT class. Just like the previous contributor I went from Basic straight to AIT, but I know some people got some time off, (furlough), between Basic and AIT.
Agricultural surplus; specialization of labor; system of laws; system of religious beliefs; natural resources and or trade; adequate military or other defense system; relatively homogenous population, just to name a few.
I think that's a Jim-Dandy start of a paper! I think it's well thought out, well written and, as far as I know, pretty accurate. You should be proud of it! Keep it up!