This reaction involves two successive Michael reactions, and has the following steps: 1. Deprotonation forms enolate ion 1; 2. The first Michael reaction forms enolate ion 2; 3. The second Michael reaction forms enolate ion 3; 4. Protonation leads to the final product. Write the mechanism out on a sheet of paper, and then draw the structure of enolate ion 2.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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