Answer:
Read Exp:
Explanation:
Barack Obama was the first African-American ever to be elected president.
The answer is <span>. propranolol; norepinephrine
Propranolol is a beta blocker that will influence the receiver's blood criculation by affecting the operations in veins and arteries.
Norepinephrine, on the other hand, is functioned in order to regulate the hormonal and neurotransmitter function in our body.</span>
These are the basics. if you want more just look online