Q: What is used to darken images of the sky? A:

OPTIONS:
- close-up filter
- uv filter
- neutral density filter
- polarizing filters

Answer: polarizing filters

Q: What are ingrowths on arthropod exoskeletons to which muscles attach? A:

OPTIONS:
- joints
- pores
- rods
- apodemes

Answer: apodemes

Q: What type of muscle makes up most of the heart? A:

OPTIONS:
- chest muscles
- heart muscle
- respiratory muscle
- cardiac muscle

Answer: cardiac muscle

Q: What type of learning is based on past experience and reasoning? A:

OPTIONS:
- experiment
- theory
- reflect
- insight

Answer:
insight