Assume that (i) the size of each disk block is 8KB, (ii) the probability that the buffer manager can handle a data request without accessing the disk (i. e., the probability that a requested block is already in the buffer) is 90%, (iii) only 10% of disk block accesses require a disk seek (i. e., 90% of the disk blocks are read consecutively without requiring any disk seek), (iv) no disk blocks are updated (i. e., no need to write dirty blocks back to the hard drive), and (v) the time spent for reading/writing data in the main memory is negligible (considered 0 milliseconds). Under these assumptions, calculate the expected data access time (i. e., how much time it would on average take to obtain a disk block from the buffer manager).

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