Answer:
To answer this question you will need the volume of the wooden box.
Explanation:
Then you will need to find out what 2/3 of that volume is because that is how full the soil will be.
V = 2/3 (16 x 12 x 28)
V = 3584 in.³
Another way to calculate this would be to find 2/3 of the Height (2/3 x 12 = 8 in) and use this in your calculation for the height.
hope this helps