$$2$$-chloro-$$2$$-methylpentane on reaction with sodium methoxide in methanol yields:

The product of the reaction given below is :

In the Hofmann bromamide degradation reaction, the number of moles of NaOH and Br₂ used per mole of amine produced are:

Which one of the following complexes shows optical isomerism?
(en = ethylenediamine)