In this problem, you have to calculate the number of disk accesses required in the worst case for different index organizations. The database keeps track of different pieces of information for a student: name (20 bytes), id number (20 bytes), GPA (15 bytes), and address (100 bytes). There are four hundred thousand students (it is a large university!). Each block can store 1500 bytes of information. A block pointer requires 12 bytes. The data file is sorted by the primary key, the student name. The id number is a secondary key. How many disk accesses are required if:
(a) access is through student name and there is no index
(b) access is through student name and there is a primary index on student name which also has to be kept on disk.
(c) access is through student name and there is a primary index on student name. You can assume that the index is small enough to be kept in RAM and is already in RAM.
(d) access is through student name and there is a 2-level primary index on student name in which the second level of the index is in memory, while the first level of the index is on disk.
(e) access is through student id and there is a secondary index on the student id which also has to be kept on disk.