You would use biuret reagent if you wanted to test an unknown sample for the presence of proteins, and a negative result would be a colored solution.

phylogenetic tree is the tree of life or evolution tree. it shows the different branches of evolution. the sequence goes like tissues - coelom - backbone - endoskeleton - segmentation

your answer is "the 1950's"

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.

dont know just give me brainliest