Question: Q: Echinoderms lack what type of system that in humans consists of the brain and spinal cord? Choices: - autonomic system - endocrine system - peripheral nervous system - centralized nervous system A:
Answer: centralized nervous system

Question: Q: What kind of process is boiling? Choices: - chemical - spheroidal - cavitation - isothermal A:
Answer: isothermal

Question: Q: Since europeans settled in the united states, about what percentage of topsoil has eroded away? Choices: - 42 percent - 10 percent - 25 percent - 33 percent A:
Answer:
33 percent