Arturo says that some plastics are made by chemically joining the same molecule to itself. Ida says that some plastics are made by chemically joining different molecules in an alternating pattern. Who is correct?

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

The grooves or folds of the brain are called

If blood contains 150g of hemoglobin per liter of blood, how much hemoglobin would be contained in 10 ml of blood