Quantity I: The ratio of the cost price to the selling price of an article is 7:11. Calculate the % profit made on the article. Quantity II: An article is purchased for Rs.1250, marked up by 50% above its purchase price, and sold after applying a 10% discount on the marked price. Determine the profit %. Quantity III: An article is sold for Rs.1580. The shopkeeper allows a 20% discount on the marked price, which was initially set with a 40% markup on the cost price. Find the profit %.