On average, each American produces 4 pounds of trash each day (1,460 pounds of trash each year). To contain this trash, landfills are constructed. In what way do landfills primarily endanger ecosystems? A. They inhibit the recycling of materials, such as aluminum or paper. B. They could decrease the production of acid rain. C. They could contaminate surface and ground water sources. D. They encourage the rapid spread of infectious diseases.

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

What can be found in every skeletal muscle? a. nerves, bones, cartilage, and connective tissue b. tendons, cartilage, nerves, and blood vessels c. muscle fibers, nerves, connective tissue, and blood vessels d. tendons, nerves, blood vessels, and bones

Me the formula cacl2 represents the compound