Mutual Funds Suppose that in a certain year, the Phoenix/Zweig Advisors Zweig Total Return fund (ZTR) was expected to yield 3%, and the Madison Asset Management Madison Strategic Sector Premium fund (MSP) was expected to yield 8%. You would like to invest a total of up to $80,000 and earn at least $3500 in interest. Draw the feasible region that shows how much money you can invest in each fund (based on the given yields). (Place ZTR on the x-axis and MSP on the y-axis.)