Which of the following would make a good semiconductor?
a. aluminum
b. germanium
c. gold
d. concrete

Which best describes red blood cells? a. they are colorless b. they protect against disease-carrying microorganisms c. they transport oxygen throughout the body d. they aid in blood clotting

Which of the following represents the chemical reaction of hydrazine and hydrogen peroxide to produce nitrogen and water? a. nitrogen + hydrogen peroxide → hydrazine + water b. nitrogen + water → hydrazine + hydrogen peroxide c. hydrazine + hydrogen peroxide → nitrogen + water d. water + hydrogen peroxide → nitrogen + hydrazine

Plants that have reproductive structures called cones are?