From "Different Rates" Section:

3. Quid Pro Quo moves $1,500,000 installments, every six months, into a tax haven account for the past six years, where it earns interest on a semiannual basis. The first four installments earned a nominal rate of 8%, the next four installments earned a nominal rate of 6%, and the last four installments earned a nominal rate of 10%. What is the current value of the account?