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Which term describes this reaction?

A skeletal diagram of a branched chain of carbons with 1 carbon bonded to O H; right arrow with H 2 S O 4 above and heat below, skeletal diagram with 2 carbons double bonded and branches above left and right and below left and right.
addition
condensation
elimination
substitution

Well, I'm not sure how to answer this but I will try. (:

Explanation:

H2SO4 and OH are compound element, meaning there are more than one elements inside. These stand for Hydrogen 2, Sulfur, and Oxygen 4 (H2SO4) and Oxygen and Hydrogen (OH).

Sorry but that's all I can answer... I hope it helped though! C:

the oldest known insects are believed to live around 400 millions ago as suggested by the fossil records.   some plants having woody stems also evolved during this time.

after the evolution of insects the first four legged species or the tetrapods evolved in shallow freshwater habitats from the intermediate species approximately 397 million years ago. the tetrapods went on conquering the land giving rise to amphibians, reptiles, mammals and birds.

the major split in tetrapods first occurred 340 million years ago branching off from amphibians.

363 million years ago when the carboniferous period began the insects started roaming on land and taking flights, following which the four limbed tetrapods adapted in the terrestrial habitat.