Gaps in rock layers are called a. unconformities c. half-lives b. index fossils d. none of the above select the best answer from the choices provided a b c d

It's unconformities. So A is correct.

a. unconformities

Explanation:

Uncinformity is a geological disturbance. It can be found as a gap between the rocks due to the deposition of sediments inside the rocks. The rocks which exhibit unconformity are generally younger than the one buried below.

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.