As you know, a single CPU processes one instruction at a time. Adding a second CPU (or core, in current terminology) allows the system to process two instructions at a time, simultaneously, effectively doubling the processing power of the system. A third core will offer triple the processing power of a single PU, and so on. However, studies have shown that, in general, the expected increase in computing power starts to decline when the number of cores grows large, beyond eight or so. Why would you expect this to be the case? For what types of computing problems might this not be true?