17 - https://drive.google.com/file/d/1cvLGeuSPaEAPkzs5-LIu0UiaExkAP-wX/view?usp=sharing
18 - https://drive.google.com/file/d/1EBeGuAiH8zvnlz1-zM5mG8khgEgFuK84/view?usp=sharing