a$)$ Consider the EMPLOYEE Relation shown belowa$)$ Consider the EMPLOYEE Relation shown below

E$.$No$.$GenderDNameENameGrade

$522,$M$,$Sales,Mathew,A$,$

$524,$

F$,$Customer care,Claire,B

$525,$F$,$Sales,Julict,B

$527,$M$,$Production,Albert,C$,$

$530,$M$,$Production,Edison,A$,$

$533,$F$,$SalesElizabeth,A$,$

$535,$F$,$Production,Marie,

A$537,$M$,$Customer care,einste Einstein $,$B

Explain bitmap indexing and how it can be used to answer the following query:"Find the ENames, who are working in 'Production" department and having A grade."$($Show how the query is answered using bitmap operations and the obtained result