Ques: Q: Toxic compounds in the environment have the most severe impact on animals that are top-level what? Choices: - vegetarian - herbivores - omnivores - carnivores A:
Ans: carnivores

Ques: Q: What is the largest mineral group, comprising over 90% of earth's crust? Choices: - oxides - carbonates - soils - silicates A:
Ans: silicates

Ques: Q: Cycling, shoveling snow and cross-country skiing are examples of what kind of heart-strengthening activity? Choices: - metabolism - anaerobic - exercise - aerobic A:
Ans: aerobic

Ques: Q: Aquatic producers need nutrients and what dissolved gas, which is more abundant near the surface of water? Choices: - helium - nitrogen - methane - oxygen A:
Ans:
oxygen