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DRAFT y +1/1/60+ y Student ID (Matricola) 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Computing Infrastructures Course 095897 M. Gribaudo, R.Mirandola 25-06-2016 Last Name / Cognome: ................................................................. First Name / Nome: ................................................................. Answers must be given exclusively on the answer sheet (last sheet): DO NOT FILL ANY BOX IN THIS SHEET Students must use pen (black or blue) to mark answers (no pencil). Students are permitted to use a non-programmable calculator. Students are NOT permitted to copy anyone else’s answers, pass notes amongst themselves, or engage in other forms of misconduct at any time during the exam. Students are NOT permitted to use mobile phones and similar connected devices. Scores for the multiple-choice part: correct answers +1 point, unanswered questions 0 points, wrong answers -0.333 points. You cannot keep a copy of the exam when you leave the room. y For your examination, preferably print documents compiled from auto-multiple-choice. y DRAFT y +1/2/59+ y Disks A HDD has a rotation speed of10000 RPM, an average seek time of4 ms, a negligible controller overhead and transfer time of256 MB/s. Files are stored into blocks whose size is4 KB. Question 1 The rotational latency of the disk is: A 0.015259 ms B 3 ms C 6 ms D 0.038147 SOLUTION: The rotational latency is half of the time required to perform one rotation: Tl = 60000 2·10000 = 3 ms. Question 2 The time required to read a400 KB file divided into5 sets of contiguous blocks is: A 36.526 ms B 51.526 ms C 701.53 ms D 1001.5 ms SOLUTION: Since the file is divided into5 sets of contiguous blocks, latency and seek times are spent5…