It is believed that early humans crossed the to get to north america.

74.It is believed that early humans crossed that to get to North America. Long time ago, our earth is filled with ice that connects all places around the world. Thus early humans crossed through frozen waters to migrate from one place to another. Since this is the scenario long years ago, I believe that early humans also crossed on the ice to be able to get to north America and live there for a period of time. That is what History is telling us about our ancestors and our mother earth.

Answer (d) may increase or decrease porosity through dissolution or deposition;