Two friends, Abhishek and Avinash playing with a catapult (gulel) decided to pluck mangoes from mango trees in their garden with the help of catapult. They collected many mangoes. Abhishek was directing the catapult on a bird sitting on a tree. But Avinash prevented him from doing so. (i) Which energy is possessed by the stretched string of the catapult? (ii) What will happen if the stone is thrown without stretching the string of the catapult? (iii) Which quality was showed by Avinash in preventing the bird from striking?