Swamps differ from marshes in that swamps a) are dominated by trees and shrubs b) are dominated by grasses and rushes c) have acidic soil d) are rich in waterfowl

A) are dominated by trees and shrubs.

Swamps and marshes both are wetlands. Swamps are wetlands, which are occupied and dominated with woody trees such as mangroves and cyprus trees and shrubs whereas the marshes are not occupied with woody trees instead they exhibit reeds, grasses and sedges. The swamps are more deeper wetlands than the marshes hence, supports the growth of the trees.

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.