1) breathing
2) emotional stress
3) physical stress
4) vagal stimulation
5) medications
6) illness
7) diseased heart
Answer:
i think b and c. but not sure what the third is? only 70% sure.
Explanation:
Answer:
it is Basic brooooooo. No B NOT C AND NOT D. oNly A
It talks about density!
I guess !
XD
The answer is "At least 15".
