An investment firm recommends that a client invest in bonds rated AAA, A, and B. The average yield on AAA bonds is 4%, on A bonds 5%, and on bonds 8%. The client wants to invest twice as much in AAA bonds as in B bonds. How much should be invested in each type of bond if the total investment is $13,000, and the investor wants an annual return of $680 on the three investments. The client should invest $ in AAA bonds, $ in A bonds, and in B bonds