Please explain throughly. Explain where each number comes from to understand.Given a relation EMPLOYEE with $150,000$ tuples, stored in $3,000$ pages:

EMPLOYEE$($EID$,$ Name, DeptID, Email, Salary$)$

Each of the $5$ attributes requires the same storage space. An unclustered tree index, with fanout

$F($i$.$e$.,$ each tree node has $F$ child nodes$),$ is created for the search key Dept$/$D$.$

Estimate the number of disk pages required to hold the data entries assuming Alternative $2$ is

used. You can ignore the pointer $($i$.$e$.,$ rid$)$ associated with each data entry in your estimation.

If the pages for the data entries have an occupancy of $75\%($i$.$e$.,25\%$ of each page is empty$),$ how

many pages are required to hold all the data entries? How many data entries are in each page?

What is the $\frac{1}{O}$ cost for finding the

$60$ matching data entrigs for department $\text{'}121\text{'}?$

What is the total I$/$O cost for retrieving the data records of the $60$ employees in Department $121?$

How many data records are in each page of the file for the EMPLOYEE table $?$

What is the total I$/$O cost for retrieving the data records of the same $60$ employees if a clustered

index on DeptID is used?