How are sedimentary rocks made? O Magma or lava is cooled.
Materials are pressed together.
Chemical reactions change minerals.
O Earthquakes cause small pieces to fall.

this would be a math

the correct answer is b

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.