Which is the layer underground where there are no empty spaces for water or air to fill in? O A. Zone of aeration
O B. Zone of saturation
O C. Impermeable rock
O D. Water table

The answer would be a.

1. why do astronomers think that there may be other advanced civilizations?
because  it was discovered that there are other planets like earth out there, able to  accommodate life forms.
2. what technologies are astronomers using to look for life on other planets? why?  
they  have used radio telescopes, but now they use laser telescopes   to track laser communications.

Is this science or geogrpahy ? ? a little confused

the answer is a i just took the test on study island

hope i