an investment firm recommends that a client invest in bonds rated AAA, A$,$ and B$.$ the average yield on AAA bonds is $5\%,$ on A bonds $6\%,$ and on B bonds $9\%.$ 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 $$28,000$ and the investor wants an annual return of $$1,740$ on the three investments