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Hydrogenation of alkenes and alkynes tak...

Hydrogenation of alkenes and alkynes takes place in presence of certain catalysts. In Sabatier Senderen's reaction, the addition of hydrogen takes place I presence of Raney nickel catalyst. Platininm and palladium can also be used as catalyst and used in finley divided state. Experimentally, it is observed that less crowded alkenes adsorb `H_(2)` with faster rate. Controlled hydrogenation of alkyne `H_(2)` with faster rate. Controlled hydrogenation of alkyne in presence of Lindlar's catalyst yields cis product i.e., 'cis' alkene. Thus, in presence of Lindlar's catalyst 'syn' addition takes place. The relative rate of hydrogenation follows the order:

Non-terminal alkynes are reduced in presence of Na or Li metal dissolved in liquid ammonia. In this reaction, anti-addition of hydrogen results into the trans-product.
Answer the following questions:
The relative rate of catalytic hydrogenation of following alkenes is:

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