-- Find minimal price for all products with units_in_stock > 30
SELECT MIN(unit_price)
FROM products
WHERE units_in_stock > 30;
-- Find product with max units_in_stock with price > 30
SELECT MAX(units_in_stock)
FROM products
WHERE unit_price > 30;
-- Calculate average count of days needed for USA shipment starting from order_date
SELECT AVG(shipped_date - order_date)
FROM orders
WHERE ship_country = 'USA';