According to the diagram, which feature is older than the other choices listed?

a

b

c

d

answer: 21

step-by-step explanation:

divide 630 by 30. 30 goes into 630 21 times

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.