Need help ASAP please!

Instructions:

Demonstrate mastery of Aggregate functions, grouping, and SQL joins.

/* Use the Murach AP database to produce the requested result sets. 1. Produce a result set that shows which vendors are being paid from more than 1 account. 2. Write a query that returns the Count of Invoices for each vendor 3. Write a query that returns the InvoiceNumber and balance due for every invoice that has a balance. 4. Write a query that returns the total amount invoiced for each Account. 5. Write a query that calculates the average invoice amount for the vendors in California. 6. Write a query that returns the Sum of the Invoice Totals for Each Vendor 7. Write a query that returns the Average of Invoice Totals for all invoices ordered by region of vendor. 

*/ 

What is wrong with this:

SELECT vendor_name, COUNT(DISTINCT li.account_number) AS "Number of Accounts" FROM vendors v JOIN invoices i ON v.vendor_id = i.vendor_id JOIN invoice_line_items li ON i.invoice_id = li.invoice_id GROUP BY vendor_name HAVING COUNT(DISTINCT li.account_number) > 1 ORDER BY vendor_name

select v.vendor_id, v.vendor_name, count(i.invoice_id) from invoices i join vendors v on v.vendor_id = i.vendor_id group by v.vendor_id, v.vendor_name

select invoice_number, (invoice_total - payment_total) as balance from invoices where (invoice_total - payment_total) > 0 and invoice_due_date between GETDATE() and DATEADD(DAY, 30, GETDATE())

select li.account_number as "account number", sum(li.line_item_amount) as "line item total" from invoice_line_items li group by li.account_number;

Select COUNT(invoice),AVG(invoice_amount) from Accounts_Details Where State = 'California' Group by vendors

Select Sum(Invoice ) from Accounts_Details Group by vendors

Select avg(Sum(Invoice )) from Accounts_Details

error I get:

Msg 207, Level 16, State 1, Line 4 Invalid column name 'vendor_id'. Msg 207, Level 16, State 1, Line 4 Invalid column name 'vendor_id'. Msg 207, Level 16, State 1, Line 13 Invalid column name 'vendor_id'. Msg 207, Level 16, State 1, Line 13 Invalid column name 'vendor_id'. Msg 207, Level 16, State 1, Line 14 Invalid column name 'vendor_id'. Msg 207, Level 16, State 1, Line 14 Invalid column name 'vendor_name'. Msg 207, Level 16, State 1, Line 11 Invalid column name 'vendor_id'. Msg 207, Level 16, State 1, Line 11 Invalid column name 'vendor_name'. Msg 207, Level 16, State 1, Line 11 Invalid column name 'invoice_id'. Msg 207, Level 16, State 1, Line 17 Invalid column name 'invoice_total'. Msg 207, Level 16, State 1, Line 17 Invalid column name 'payment_total'. Msg 207, Level 16, State 1, Line 18 Invalid column name 'invoice_due_date'. Msg 207, Level 16, State 1, Line 18 Invalid column name 'invoice_due_date'. Msg 207, Level 16, State 1, Line 16 Invalid column name 'invoice_number'. Msg 207, Level 16, State 1, Line 16 Invalid column name 'invoice_total'. Msg 207, Level 16, State 1, Line 16 Invalid column name 'payment_total'.

NEED ASAP!

Thank you