2. Circle only one correct answer in each of the following two questions: a) In the 2009 Top 500 list of fastest computers systems, which architecture dominates? i. Symmetric shared-memory multiprocessor systems ii. Centralized massively parallel processor systems iii. Clusters of cooperative computers b) In a cloud formed by cluster of servers, all servers must be selected as follows: i. All cloud machines must be built on physical servers ii. All cloud machines must be built with virtual servers iii. The cloud machines can be either physical or virtual servers