Use the Variance $$ Covariance matrix in the Excel file: Efficient Portfolios Data.

Construct a model to determine the following:

a$.$ Calculate an envelope portfolio assuming the risk$-$free rate is $4\%.$

b$.$ Calculate an envelope portfolio assuming the risk$-$free rate is $14\%.$

c$.$ Using EXCEL$$s Data Table Feature, create a one$-$way data table that determines the different means and standard deviations for combinations of Envelope Portfolio $1$ and Envelope Portfolio $2$ by varying the proportion of Portfolio $1$ from $-6$ to $+6$ in increments of $0\mathrm{.}60.$

d$.$ Graph the combinations of the portfolios from the one$-$way data table and add the individual asset means and standard deviations to the graph.

e$.$ Provide a title on the graph and label the axes of the graph.

f$.$ Using EXCEL$$s Text Box feature, explain whether the portfolio combinations could be on the efficient frontier.

g$.$ The efficient frontier is said to provide $$a set of equally good portfolios$$ for investors. Use EXCEL$$s Text Box feature to explain the meaning of this statement?