Multicellular plants and unicellular algae have one important feature in common. What is it? A) They contain chlorophyll. B) They reproduce by cell division. C) All are made of one or more cells. D) The cells of each contain exactly the same parts.

a polymer is a chainlike molecule made up of small molecular units. these small molecular units are called monomers. monomers of polymer can be joined together either naturally or synthetically.  

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.

the sun's light combined with the visible wavelenghts form what is called ultraviolet radiation, which are the long waves at the end of a visible light sprectrum.

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bioteacher101