Parafocus shooting --- Introduction ---

This is a visual exercise about the parabloa focus. Given a picture of a parabola, your task is to click on the point in the picture which you think is the focus of the parabola.

At the end of a session composed of several shots, you will be given a score computed according to the average precision of your shots during the session.

Choose a level of difficulty to start your exercise: 1 , 2 , 3 , 4 , 5 .

There is also a detailed menu for the parameters of this exercise. The most recent version

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