Allene (1,2-propadiene) has point group D2d, itself is achiral because it has two planes of symmetry. ... An allene with substituents on one terminal carbon atom are unlike and substituent on other terminal carbon atoms are same, allene will be achiral. It will have one symmetry plane.
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Answer: Climax Commuity.
Explanation: (hope it’s right! Good luck!)
The available energy decreases as one moves upward in an energy pyramid.
<h3>Energy pyramid</h3>
The energy pyramid represents a model of how energy is transferred from one trophic level to another in ecosystems.
Energy is transferred from producers to primary consumers, from primary to secondary consumers, from secondary to tertiary consumers, and so on.
Only about 10% of the available energy in one trophic level is transferred to the next with the remaining 90% being lost as heat to the environment.
Thus, as one moves up the energy pyramid, the available energy decreases. This is why organisms at the higher end of the energy pyramid have to devise an efficient way of extracting energy from their foods.
More on energy pyramid can be found here: brainly.com/question/2515928
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