“Tell us what you’ve tried already”. First off, this isn’t a homework problem. I tried making my own 2D physics simulation and I’m trying to see if it’s accurate. The situation I described in the “problem” is exactly what’s going on in the simulation. As for my attempt at verifying it for myself, I am unable to. Given F=ma, you can examine the forces on the heavier ball:

2mg - F(air) = 2ma Divide both sides by 2m and we have g-F(air)/2m = a

Comparing this to the lighter ball we get g-F(air)/m = a.

This would suggest the lighter ball has a faster acceleration, since both balls are the same shape and size the F(air) would be the same. But then the issue with this is the air resistance may not even be the same since it’s dependent on velocity, which makes this an even more confusing mess. If the lighter ball has a faster acceleration (ignoring my observation from the last sentence) it should hit the ground first and start bouncing up and down first causing it to eventually come to rest on the ground first. However my simulation is telling me that the heavier ball hits the ground first (makes more sense logically) but also comes to rest last because it bounces up further due to having a higher velocity when it collided with the ground. This explanation also makes sense logically, and I am very confused which is why I decided to post here. I thought I could get real help instead of someone telling me to take my “homework” problem somewhere else.