What is atomic mass equal to? 

A)  the sum of the neutrons and protons 
B)  the sum of the neutrons and isotopes 
C)  the sum of the neutrons and electrons 
D)  the sum of the protons, neutrons, and electrons

The main way water gets into a subduction zone is by:

A) heating of the overlying continental crust
B) a decrease in pressure that causes melting
C) rain associated with eruptions in the island arc
D) seawater introduced into oceanic crust at the mid-ocean ridge, prior to subduction
E) all of these