$)$ The Standing Stone Credit Union has $$250,000$ available to invest in a $12-$month time window. The money can be placed in Canadian treasury notes yielding an $8\%$ return, or in high$-$yield bonds with an average rate of return of $9\%.$ Credit union regulations require diversification to the extent that at least $50\%$ of the investment be placed in treasury notes. Also, regulations require that no more than $40\%$ of the investment be placed in bonds. How much should the Standing Stone Credit Union invest in each security so as to maximize its return on investment? Formulate this problem as a linear program and solve.