28) Consider six files F1, F2, F3, F4, F5 and F6 of corresponding sizes 100, 200, 70, 40, 250 and 50 respectively. If the files are stored in such a manner to optimize access time, what will be the approximate average access time of a record from one of the six files on the sequential device ?

29) In MS-DOS, relocatable object files and load modules have extensions

30) Primitive disk operating system (POS) manages its disk files in contiguous blocks. A file is saved to the first available space that is large enough to hold the file. Assume that a disk has only 10 contiguous blocks of available free space. Which of the following set of file operations Fa=1, Fb=3, Fc=5, Fd=6 can not be completed given the set of files and file sizes specified below

31) A file sometimes called a

32) A program P reads and processes 1000 consecutive records from a sequential file F stored on device D without using any file system facilities. Given the following:
(i) Size of each record = 3200 bytes.
(ii) Access time of D = 10 m secs.
(iii) Data transfer rate of D = 800 x 103 bytes/sec
(iv) CPU time to process each record = 3 m secs.
What is the elapsed time of P if F contains unblocked records and P does not use buffering?