How much is the black wolf slingshot saw?

150 cm. Slingshots have been produced since ancient times. In order to catch food, apes threw stones at their prey. The stone was placed on the bow line from which the shells were fired. The distance between the black wolf slingshot and the bow is 150, and the bow is pushed forward. The upper and lower rubber bands overlap. When he saw the upper belt, he couldn't see the rubber bands below, indicating that they were overlapping. Then he pulls the rubber band to his ear or passes it.