Find the points of local maxima and minima if any of the following function defined in $$0 \le x \le 6,$$ $$\,\,\,\,f\left( x \right) = {x^3} - 6{x^2} + 9x + 15.$$

In a resident $$–OS$$ computer, which of the following systems must reside in the main memory under all situations?

When the result of a computation depends on the speed of the processes involved there is said to be

A counting semaphore was initialized to 10. Then 6 P (wait) operations and 4 V (signal) operations were completed on this semaphore. The resulting value of the semaphore