During an appearance at the Goldman Sachs Investment Symposium, Apple COO Tim Cook spoke about the iPod and iPhone, and calmed investors by stating that the company is on track for its goal of ten million units sold by the end of the year. “We are right on track for where we want to be,” Cook said. “The four million units we’ve sold over the first 200 days gives us confidence that we can achieve ten million units in 2008.”…