What major engineering feat helped keep Roman cities clean?
A. power washers to wash down the buildings and streets
B. latrines for public waste
C. indoor plumbing and sewers to keep human waste out of homes and streets.
D. street sweepers to sweep the streets of debri

A. power washers to wash down the buildings and streets

Explanation:

The atomic model is our understanding of how the atom is structured. At one point in history, people believed that any substance was simply made of that substance and would retain that property no matter how small a quantity it was reduced to. Later, some argued that all matter was made of tiny particles called atoms. While this is correct, later researchers found that even the atoms were made of smaller particles called electron, protons, and neutrons. More recently, scientists have discovered quarks, tiny particles that makeup protons and neutrons.