Some bacteria living in the ocean floor can turn methane (a gas) into food. How would you classify these bacteria? A. producers
B. consumers
C. decomposers
D. both consumers and decomposers

"d.) carbon dioxide and hydrogen sulfide"

oxygen +1 most likely

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.