You could go in as a Second Lieutenant, if you wished to go the officer route.
You could enter as an Ensign if you wanted to go the officer route.
Lieutenant Commander
Yes. If you get ordained, you could even enter as a chaplain with a commissioned officer rank.
no
He is the fourth African American Marine to attain that rank.
There are no ranks in the Air Force that require an Associate's degree. To become an officer you must have a minimum of a Bachelor's Degree. To enlist you must have at least a high school diploma or GED. While you're enlisted you can work on school using tuition assistance to obtain an Associate's degree but it does not change your rank or pay grade. If you already have an Associate's degree and you want to enlist you may be offered to enter with a higher rank/pay grade (i.e. E-2 or E-3).
Going the standard route, and not going in as a direct commissioned officer whose rank is based on experience accrued in a civilian equivalent to their military occupation, you would go in as a Second Lieutenant,
it varies, they must pass certain qualifications to rank up. but some rank up from private to general in about 30 years if they're good at what they do.
Rank is not determined by academic qualifications.
that depends on which country.
The highest rank in the Marines, by title and rank, is the Commandant of the Marine Corps. The position is currently held by 4-Star General James T. Conway. The position holds 4-Star General rank, regardless of the officer's actual rank. For example, a 2 or 3 star General can be selected and confirmed by the Senate for that position, and thereby gains 4-Star rank by virtue of holding that position, but would revert to their former rank when they left. That's why most retire after serving (your pension is based on highest rank achieved), though not all do.
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