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Question

Consider a disk with block size B=512 bytes. A block pointer is P=6 bytes long, and a record pointer is PR =7 bytes long. A file has r=16384 STUDENT records of fixed-length. Each record has the following fields: 
NAME (30 bytes), ROLL(9bytes), DEPARTMENT(9 bytes), ADDRESS(40 bytes), 
PHONE (10 bytes), DOB(8 bytes), CLASS(4 bytes), 
Two additional bytes are used as markers. Multilevel indexing is used. 
If the file is ordered using ROLL value, the number of block accesses needed to search for and retrieve a record from the file is:

a)3

b)4

c)5

d)6