A. Write an SQL statement to show the sum of Sub Total (this is the money earned by HSD on products sold exclusive of shipping costs and taxes) for INVOICE as Sum Of Sub Total. B. Write an SQL...

A. Write an SQL statement to show the sum of Sub Total (this is the money earned by HSD on products sold exclusive of shipping costs and taxes) for INVOICE as Sum Of Sub Total.

B. Write an SQL statement to show the average of Subtotal (this is the money earned by HSD on products sold exclusive of shipping costs and taxes) for INVOICE as Average Of Sub Total.

C. Write an SQL statement to show both the sum and the average of Subtotal (this is the money earned by HSD on products sold exclusive of shipping costs and taxes) for INVOICE as Sum Of Sub Total and Average Of Sub Total respectively

D. Write an SQL statement to modify PRODUCT Unit Price for Product Number VK004 to $34.95 instead of the current Unit Price of $24.95.