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when and how did h2o come to earth?

hi there!

answer: b. nucleolus

explanation: nucleolus is a structure in the nucleus are ribosomes are made.

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have a nice day! : )

: d

-charlie

you! : )

: d

not only is it colder, it also becomes darker, less salty, and more dense.

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.

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.