Answer:
A buffer
Explanation:
A buffer is composed of a weak acid and a conjugate base. They are resistant to pH because of equilibrium between the acid and its conjugate base.
Answer:
B) Valves closing
Explanation:
A healthy heart makes a lub-dub sound with each beat. This sound comes from the valves shutting on the blood inside the heart. The first sound (the lub) happens when the mitral and tricuspid valves close.
It's definitely letter A. Mononucleosis
Its called the hypothalamus or neurons
both mean the samething
Categories of age, sex, race, and urgency of admission, are all risk to a nosocomial infection