A dry soil sample has a volume of 500 mL. After 400 mL of water are added to the soil, the soil becomes saturated with 150 mL of surface water left on top. What is the porosity of the soil?

Transportation is the largest single source of air pollution in the united states. air pollution can harm the environment and human health. which technology could offer a solution to this problem? mufflers that reduce noise motors that run on electricity tires that improve gas mileage

In the cathode ray tube experiment, j. j. thomson passed an electric current through different gases inside a cathode ray tube in the presence of an electric field. in which two ways did this experiment change scientists’ understanding of the atom?

State one important difference between a physical change and a chemical change?