Fake Coins and a Magic Bag You have a collection of coins consisting of 5 gold coins, 5 silver coins, and 5 bronze coins. Among these, exactly one gold coin, exactly one silver coin, and exactly one bronze coin are counterfeit. You are provided with a magic bag that has the following property. Property When a subset of coins is placed into the bag and a spell is cast, the bag emits a suspicious glow if and only if all three counterfeit coins (the gold, the silver, and the bronze) are included in that subset. Determine the minimum number of spells (i.e., tests using the magic bag) required to uniquely identify the counterfeit gold coin, the counterfeit silver coin, and the counterfeit bronze coin.