According to the conceptual$/$physical model, all required is the SQL code AND two screenshots of outputs of these two queries in Oracle SQL Developer, one for Query$1$a$)$ and one for Query$1$b$),$ but since I couldn't send the data of these tables, I just want you to write the SQL code and see all the screenshots and my descriptions in this text. Please, read carefully and make sure the queries are correct and executable:

$1$a$)$ Create OLAP cube with the following dimensions: year of rental, customer address, car class. Summary of rental cost is fact attribute.

OLAP cube should include data only from $2010$ and $2011$ years and only for customers who address has letter $\text{'}$t$\text{'}$ in customer's address.

Sort data by year, address, class.

$1$b$)$ With OLAP cube made in $1$a:

$-$ modify to see only:

$-$ totals for each year, each address and each class.

$-$ grand total from all dimensions.

$-$ add grouping columns for every attribute to see if NULL is generated by DBMS;

$-$ show grouping level;

$-$ check if there is duplicated data;