Question

organisms on land at sea level are under _______________ of pressure.
1 ppt
5 atm
1 atm
10 atm

Explanation:

Atmospheric pressure at sea level is defined as 1 atmosphere (atm). Ppt (parts per thousand) is a unit for concentration, not pressure. 5 atm and 10 atm are higher pressures than standard sea - level pressure.

Answer:

1 atm