If a box full of feathers and a box full of bricks were to be dropped at the same time and from the same height, which one would hit the ground first?

They would hit to ground at the same time. This is because they would both accelerate to the ground at 10m/s^2 due to gravity regardless of what their mass is. This is contrary to one might intuit when considering a falling feather vs a falling brick, as the feather would hit the ground first in that scenario, that is because the force due to air resistance has a bigger effect on a feather because it is less dense than the brick.