Hello, Need some help with the following Oracle SQL questions:

Write a SELECT statement to return one column from the vendors table named Full Name. Create this column from the first name and the last name columns and format it like this: last name, dash, space, first name (for example, Smith - Joe). You dont have to worry about the case of the strings. Next, sort the results by vendor_name. Then, filter result set for contacts whose last name (vendor_contact_last_name) start with the letter A, X, Y or Z.

Write a SELECT statement that returns invoice_id, vendor_id and payment_total and payment_total + 100 from the invoices table. Name these columns Invoice, Vendor, Payment and new payment. New payment is the payment_total + $100. Filter the results set to only the data for payment_toatl between $600 and $900. Sort the results in descending order of payment_total (high to low).

Write a SELECT statement to return the balance due and the payment date from the invoices table, but only when the payment_date column does not contain a null value.

Write the statement to use the DUAL table (dont use any of the existing tables that has data in it) to create a row with the following columns: Current date using the format dd-mon-yyyy, hh24:mi:ss and the current user

Write the statement to use the DUAL table to display the result of the expression 2 * 5 + 9 16/3.