if you want to send the tank off at 500 kmph, you would need some trig to have even a chance at getting it, but i doubt it would work right anyway, due to ofp friction and other stuff, it tends to stick in place
I believe i tried teaching you some trig (along with THobson) in another thread and you gave up on it.
as for the parameters, here's how they work in a nutshell
[parameter1,parameter2,parameter3] exec "script.sqs"
that passes on those three parameters to script.sqs, which can be defined in the script.
in the script, whatever you pass to the script is defined as _this
in general, we use an array (a list inside [] brackets) and therefore to choose which one we use select:
_param1 = _this select 0
_param2 = _this select 1
_param3 = _this select 2
would then select each of the 3 parameters that you passed to the script in the array.
parameters are simply variables. they can be any value you want (string,another array, a unit, a number, etc ,etc)
you can then use whatever varible you gave that value to however you want (within the boundaries of ofp of course)
therefore if you wanted a height, you put in as a parameter and then use it where you need, if you want a variable number of units in a list, you would use another array inside the array of parameters that contains your units, and then you'd need commands like foreach which deal with arrays, or a loop that goes through each individually