'README.md' updaten

README.md

@@ -74,13 +74,3 @@ Return these columns:
 This should return 2 rows.
 
 
-### Exercise 8
-
-Write a SELECT statement that uses aggregate window functions to calculate the total due for all vendors and the total due for each vendor. 
-
-Return these columns:
-
-- The vendor id from the Invoices table The balance due (invoice_total - payment_total - credit_total) for each invoice in the Invoices table with a balance due greater than 0
-- The total balance due for all vendors in the Invoices table The total balance due for each vendor in the Invoices table
-
-Modify the column that contains the balance due for each vendor so it contains a cumulative total by balance due. This should return 11 rows.