The single$-$index model:

Multiple Choice

enhances the understanding of systematic versus nonsystematic risk and greatly increases the number of required calculations relative to those required by the Markowitz model are correct.

enhances the understanding of systematic versus nonsystematic risk.

greatly increases the number of required calculations relative to those required by the Markowitz model.

greatly reduces the number of required calculations relative to those required by the Markowitz model and enhances the understanding of systematic versus nonsystematic risk are correct.

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