What is the best definition of activation energy

The term Activation Energy was introduced in 1889 by Svante Arrhenius, a Swedish scientist. It is defined as the least possible amount of energy (minimum) which is required to start a reaction or the amount of energy available in a chemical system for a reaction to take place.

Hope that helps :)))

one is through turgidity. this occurs before ground tissue ( collenchyma

and sclerenchyma cells) become well

developed to give structural support to the plant as it grows bigger. the xylem

tissue (composed of rigid tissue) of the young

plant render this support and also maintaining osmotic turgidity of the surrounding

plant cells.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."