Respuestas
1.The overwhelming majority is unable to do so, but the weight of statistics does not prevent us from trying this possibility to try the impossible contortion.
2.Shake the ears: there is a scientific reason that explains that very few people can make this movement very evident, for example, in bats and cats. The muscles of the ears are very poorly developed in humans and in addition to having a control area in the brain, they have their own nucleus that makes it more difficult to voluntarily activate that area.
3.The trick of keeping some fingers still while moving others. The tendons of the fingers function independently except for the heart and ring. This makes it more complicated to send different orders for each of them. The exercise they pose in the video consists of placing the hand with the bent heart finger on a flat surface. Then, when trying to lift the other fingers, you will see that there is no major problem until you try the ring.