Why is the netherlands(holland)prone to floods?

Why have the aztec ruins in mexico city not been dug up?

What was one step that charlemagne took to unite his kingdom? a. he chose a single strong heir to inherit his throne. b. he drove muslim forces out of europe. c. he created and supported schools. d. he declared himself head of the catholic church.

The most likely reason why an ancient greek might worship more than one god is that?