Lactase and carbonic anhydrase are examples of what type of substance?

The answer is enzymes. Enzymes are biological catalysts and increase the speed of change from substrate to product. The name of enzymes is usually derived from the substrate they break down. For example, lactase breaks down sugar lactose. The name of enzymes contains suffix -ase, for instance, carbonic anhydrase, lactase, lipase, amylase, etc.

i got something better   a catchphrase here it is

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ahem

what the squwock

explanation:

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.