File System question: Consider a disk with 300 tracks, and the following sequence of requested tracks 80, 150, 230, 50, 220, 50, 190, 260, 210, 270. Assume that the disk arm is located at position 60 and is moving in the up position (i.e. 1 to 300). Calculate the number of tracks crossed if using the shortest seek time first disk scheduling algorithm.