二、消防水源管理工作落實與否，事關地方消防單位執行各種火災搶救工作之成敗，請詳述消防水源查察勤務執行方式及要領為何？（25 分）

3. (10%) Suppose we are playing draw poker. We are dealt (from a well shuffled deck) 5 cards which contain 4 spades and another card of a different suite. We decide to discard the card of a different suite and draw one card from the remaining cards to complete a flush in spades (all 5 cards spades). Determine the probability of completing the flush.