Enter your Vin into realoem. That will give you the build of your car.
I think the cylindrical part on the left side of the picture is a subframe bushing but you need to confirm that with a lookup.
Since I looked at the picture again, I can confirm that you don't have air suspension. The rear suspension system is coil over. It's possible that the rear strut on one side has lost it's gas charge leading to the sag.
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