Carl knows that water moves through different kinds of soil at different rates. how easily water moves through a soil is known as permeability. carl decides to compare the permeabilities of different soil types. to do this, carl takes five identical flower pots with holes in the bottom and fills each one with different soil: rocky, gravely dirt from the side of the road potting soil from the store clay soil from a nearby creek sand from a store dirt from his own backyard carl pours one liter of water into each pot and measures how much water flows out of the bottom in one minute.

To get the same same results from all pots "amount of water should be same" for all pots.

Explanation:

As Carl want to measure and compare the amount of water that flows in pot in one minute from all all pots. He should keep the amount of water constant for all pots to get the desired results.

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