Question

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. Which of the following variables should be kept constant during this experiment? (1 point) Responses A. the permeability of the soil in each pot A. the permeability of the soil in each pot B. the amount of water that goes into each pot B. the amount of water that goes into each pot C. the amount of water that comes out of each pot C. the amount of water that comes out of each pot D. the kind of soil in each pot

Answer 1

In Carl's experiment, the variable that should be kept constant is:

B. the amount of water that goes into each pot

This ensures that any differences in the amount of water that flows out can be attributed to the permeability of the different soil types, rather than variations in the initial amount of water used. Other variables, such as the type of soil, will naturally differ as that is the focus of the experiment.