Question 1. Suppose that a disk unit has the following parameters: seek time = 15 milliseconds (ms); rotational delay = 30 ms; block transfer time = 2 ms; block size = 2048 bytes; interblock gap size = 400 bytes. An EMPLOYEE file has the following fields: Ssn, 11 bytes; Last_name, 24 bytes; First_name, 24 bytes; Middle_init, 1 byte; Birth_date, 8 bytes; Address, 50 bytes; Phone, 12 bytes; Supervisor_ssn, 11 bytes; Department, 6 bytes; Job_code, 5 bytes; deletion marker, 1 byte. The EMPLOYEE file has = 10,000 records, fixed-length format, and unspanned blocking. Write appropriate formulas and calculate the following values for the above EMPLOYEE file:

Q1a) Calculate the record size (including the deletion marker), the blocking factor bfr, and the number of disk blocks b.

Q1b) Calculate the wasted space in each disk block because of the unspanned organization.

Q1c) Calculate the average number of block accesses needed to search for an arbitrary record in the file, using linear search.

Q1d) Calculate in ms the average time needed to search for an arbitrary record in the file, using linear search, if the file blocks are stored on consecutive disk blocks and double buffering is used.

Q1e) Calculate in ms the average time needed to search for an arbitrary record in the file, using linear search, if the file blocks are not stored on consecutive disk blocks.

Q1f) Assume that the records are ordered via Ssn. Calculate the average number of block accesses and the average time needed to search for an arbitrary record in the file, using binary search.