Can someone please tell me what Dynamic means and how so you know if a car has it?
Correct, you can tell a RRS with the dynamic package because it has the two wavy lines on the terrain response selector. When selected it adds weight to the steering, the active roll bars keep vehicle roll to less than one degree and throttle response is much sharper. The transmission has its own sport mode that holds gears longer and will downshift when you lift off the throttle to keep the engine in the power band as you slow down to enter a corner to provide maximum power on the exit. Also if you use the paddle shifters it will hold that gear regardless until you shift again.Few items in the dynamic package but the main one is the dynamic suspension which stiffens up when activated to provide better handling when desired (although it is a harsher ride). I also believe the dynamic changes the shifting patterns of the transmission, allowing you to get closer to redline before the auto transmission shifts.
As Mancerator says, I also think the Brembo brakes were standard on the Dynamic. Which is essentially a much bigger rotor and 6 pot brake caliper in the front.