Atest that determines the percentage of erythrocytes in a volume of blood:

i believe you meant to say air rather than hair so the answer is below ")

the dead sea, the lowest place on earth at 430 metres (1,410 ft) below sea level, has a correspondingly high typical atmospheric pressure of 1065 hpa.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.