Max cost of insertion into a sorted file, with overflow pages ...
Which query is a one=type query on the Students(id,name,phone,degree)?
The only query type that is guaranteed to produce just one result is
select * from Students where id = StudentID
Since noe of the suggested queries has this form, none of them are examples of one-type queries.
Which pages to access for a linear-hashed query (no unknown bits):
Which pages to access in a hashed file for select * from R where id > 1234;?
All of them. Hashing does not help order-based queries. Tuples are effectively stored in random order.