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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 05-09-2016 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 do cuments compiled from auto-multiple-choice. y DRAFT y +1/2/59+ y Disks Consider the following set of disks connected in RAID 6, with generator g =2 , MTTF = 1461 days, MTTR = 15 days, rotating at 8400 RPM, with an average seek of 3 milliseconds, trasfer time of 128 MB / second, and a controller overhead of 150 microseconds: !"#$%& !"#$%' !"#$%( !"#$%) !"#$%* !"#$%+ !,&!&,!',!(&,-&&./& !,&!&,!',-&&./&!(&, !,&!&,-&'./*!'&!(&,0123$%4&0123$%4'0123$%4(0123$%4)0123$%4*0123$%4+ 0123$%0&0123$%0'0123$%0(0123$%0)0123$%0*0123$%0+ 0123$%5&0123$%5'0123$%5(0123$%5)0123$%5*0123$%5+ Figure 1: A RAID 6 configuration. Question 1 What data is contained in block A6? A Q = 11 B Q = 81 C Cannot be computed D…