Which type of operant reinforcer is natural, nonlearned, and rooted in biology with food, water, and sex being obvious examples?

Damage to the frontal cortex of the brain is most likely to affect the following functions?

a. understanding and producing language c. spatial relations b. musical ability d. decision making

How many pairs of spinal nerves do humans have?

a. 31 b. 22 c. 12 d. six