Answer: 5 mL/min
Step-by-step explanation:
Amount of water = 200 mL
Percolation time = 40min
Rate of percolation = Amount of water in mL / Percolation time in min
=200 / 40
=5 mL/min.
Hence, the rate of percolation of water through the given soil sample is 5 mL/min.