Oh, that reminds me...
In the beginning BCT administers a kind of 'Junior PT Test' they call a 1-1-1... Basically, they only let you do 1min of PU, 1min of SU, and you only run 1 mile... If you can pass the real one you can pass the mini-version....
For the real test it's 2min per event, except the run, which is as listed in the run chart I posted...
The way they are SUPPOSED to execute, you have lines in front of your graders - each soldier does their pushups & gets to the back of the line, then when everyone has gone thru the pushup line they start with situps. So you get as much 'rest time' as it takes for the line to cycle around....
Could some DS decide to have you do 2min of PU & roll over? Yes, but that's not the standard...
As for the Army definition of a Pushup and a Situp, see FM-21-20 (as linked above)...
Basically, a 'pushup' is done by lowering your arms parralell to the ground, and raising your body 'as a unit' untill you lock out your arms. You DO NOT have to touch the ground, you DO NOT have to keep your arms close to your sides (ala chicken-wings), and you ARE allowed to rest (by either bending your knees & arching your back or sagging in the middle, so long as you don't rest on the ground, lift your hands, or rock back on your legs while 'arching')....
That's it in a nutshell - the only easier test to pass in the Army is the piss test...