please help using SQL plus or SQL developer

STOCK

$\backslash$table$[[$STOCK$\_$ID$,$STOCK$\_$TYPE,STOCK$\_$MODEL$\_,$MANUFACTURER$],[12345,$Desktop,Proline K$100,$Acer$],[54321,$Laptop,$J55,$Mecer$],[78945,$Server,HP$9000,$Samsung$],[98754,$Laptop,Aspire $450,$HP$],[55355311,$Notebook, L$920,$ lenovo$]]$

CUSTOMER

$\backslash$table$[[$CUST ID$,$CUST$\_$FNAMECUST$\_$SNAME,CUST$\_$ADDRESS,CUST$\_$CONTACT,$],[$C$115,$Jeff,Willis,$3$ Main Road,$0821253659],[$C$116,$Andre,Watson,$13$ Cape Road,$0769658547],[$C$117,$Wallis,Smith,$3$ Mountain Road,$0863256574],[$C$118,$Alex,Hanson,$8$ Circle Road,$0762356587],[$C$119,$Bob,Bitterhout,$15$ Main Road,$0821235258],[$C$120,$Thando,Zolani,$88$ Summer Road,$0847541254],[$C$121,$Philip,Jackson,$3$ Long Road,$0745556658],[$C$122,$Sarah,Jones,$7$ Sea Road,$0814745745]]$

REPAIRS

$\backslash$table$[[$REPAIR$\_$ID$,$REPAIR$\_$WORK,REPAIR$\_$DATE,REPAIR$\_$HOURS$],[1,$HD defragmentation,$15/$JUL$/23,2],[2,\backslash$table$[[$RAM module replaced. Time taken to$],[$diagnose problem$]],18/$JUL$/23,3],[3,$Battery Replaced,$19/$JUL$/23,2],[4,$OS Upgraded,$20/$JUL$/23,2],[5,$Faulty hard disk replaced,$25/$JUL$/23,3]]$

SALES

$\backslash$table$[[$SALES$\_$NUM,SALES$\_$DATE,SALES$\_$AMT,STOCK$\_$ID$,$CUST$\_$ID$,$REPAIR$\_$ID$],[101,27/$JUL$/23,$R $1700,98754,$C$121,3],[102,20/$JUL$/23,$R $1500,12345,$C$120,4],[103,\frac{23}{J}U\frac{L}{23},$R $1650,55311,$C$119,5],[104,17/$JUL$/23,$R $1300,54321,$C$117,2],[105,19/$JUL$/23,$R $1900,12345,$C$122,1]]$

QUESTION $1$

CREATE AND POPULATE THE TABLES

Question $2$

$($Marks: $5)$

TASK: Query Time taken to complete Repairs.

Using SQL only; display the combined customer name, the repair work, repair date and repair hours. In your query only display the results that had a repair time less than $3$ hours.

Question $3$

$($Marks: $5)$

TASK: Query Sales Made

Using $.QL,$ display the Customer ID$,$ Stock Type and the Sales Amount. In your query only display the results where the sales amount is less than R $1500.$

Question $4$

$($Marks: $15)$

TASK: Query Calculate Commission

IT Gear Dealer has a policy that states that, for any individual sale made, the employee who completed the repair work receives a certain commission.

Using PL$/$SQL$,$ display the Customer ID$,$ Stock ID$,$ Sales Number, the Repair ID$,$ the Sales Amount, and the commission payable which will be calculated as follows:

For an individual sale of R$999$ or less, apply a $5\%$ commission.

An individual sale between R$1000$ and R$1499,$ apply a $10\%$ commission.

An individual sale of R$1500$ or more, apply a $15\%$ commission.

Question $5$

$($Marks: $5)$

TASK: Create View

Create a view called Repair$\_$View that will display the combined Customer Name, Stock ID$,$ Repair Date and the Repair Work done. In your query also include the statement to run the view.

Question $6$

$($Marks: $10)$

TASK: Create Trigger

Create a Trigger called Sales$\_$Entry that will prevent a user from entering a sales amount that is less than zero. In your query include the code to test the trigger.

Question $7$

TASK: Create Stored Procedure

$($Marks: $15)$

Create a stored procedure called sp$\_$customer$\_$details that accepts sales and display the customer id$,$ customer first name, surname and their contact number.

In your solution display the data for any customer and provide the code to execute the procedure with relevant exception handling and relevant code comments.

Question $8$

$($Marks: $15)$

TASK: Create Function

Create a function called fn$\_$IT$\_$Gear that would be meaningful and relevant for this database. Your function should accept at least $1$ input$-$parameter and display at least $4$ relevant pieces of information:

In your solution,

display the data and provide the code to execute the function.

use relevant exception handling and

provide relevant code comments