Wiggins Financial manages funds for a number of companies and wealthy clients. The investment strategy is tailored to each client's needs. For a new client, Wiggins Financial has been authorized to invest up to $$1\mathrm{.}5$ million in two investment funds: a stock fund and a money market fund. Each unit of the stock fund costs $$60$ and provides an annual rate of return of $12\%$; each unit of the money market fund costs $$120$ and provides an annual rate of return of $6\%.$ The client wants to minimize risk subject to the requirements that the annual income from investment be at least $$80,000.$ According to Wiggins Financial's risk measurement system, each unit invested in the stock fund has a risk index of $7,$ and each unit invested in the money market fund has a risk index of $2$; the higher risk index associated with the stock fund simply indicates that it is the riskier investment. Wiggins Financial's client also specified that at least $$600,000$ be invested in the money market fund.

Develop a linear programming model only. Show your work!