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+133/1/43+ Computing Infrastructures Course 095897 P. Cremonesi, M.Roveri 17-06-2019 Student ID (codice persona): ............................. 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: correct answers +1.5 point, unanswered questions 0 points, wrong answers -0.5 points. Questions with multiple answers will be considered as not answered (0 points). FIORAVANTI TOMMASO Mark: 31.5/33 (total score: 31.5/33) +133/2/42+ Question 1 In the Microkernel architecture of VMs: ADrivers are part of a specific service VM BDrivers are part of the Guest VMs CDrivers are part of the Hypervisor DDrivers are part of the Guest Oss Explanation: Question 2 Gmail is an example of AInfrastructure as a service BCommunication as a service CPlatform as a Service DSoftware as a Service Explanation: +133/3/41+ In the following questions we will assume that both failure and repair events follow exponential distributions. Question 3 The analysis of the failure behavior of a two components system reveals that the system is down only when both its components are down. The two components A and B have the following characteristics: A=0.009days 1,MTTRA=6days, B=0.106days 1andMTTRB= 5days. The reliability of the system at…