4. A sorting method with "Big-Oh" complexity O(n log n) spends exactly 1 millisecond to sort 1,000 data items. Assuming that time (n) of sorting n items is directly proportional to n log n, that is, T(n) = cn log n, derive a formula for T(n), given the time TIN) for sorting Nitems, and estimate how long this method will sort 1,000,000 items