Modeling. Consider the following portfolio problem:

a$.$ What is the maximum number of portfolios that must now be considered? $($All are not

feasible$)$

b$.$ What is the optimal portfolio for an annual budget of $13$ per year?

c$.$ What is the optimal portfolio for a total budget of $65$ that can be allocated across the five

years?

d$.$ What is the percentage increase in value by removing the annual budget constraint?