What is the total price charged for orders shipped by air without shipping instructions?
SUM(MULTIPLY(MULTIPLY(l_extendedprice, SUBTRACT(1, l_discount)), SUM(1, l_tax))) where l_shipmode = 'AIR' and l_shipinstruct = 'NONE';
SELECT l_extendedprice * (1 - l_discount) * (1 + l_tax) AS totalprice FROM lineitem WHERE l_shipmode = 'AIR' AND l_shipinstruct = 'NONE'