1. The text says the human head weighs less than half a dozen kilograms.
True
False
It doesn't talk about head weight.

2. As you tilt your neck forward, the weight on your spine begins to .

3. What does spasm mean to your muscles?
the same as boom (as in explode)
the same as shorten and tighten
the same as make a loud noise

4. What is the best explanation for what wear and tear means?
something that makes you cry tears
damage that happens over time
sudden damage