Parafocus shooting --- Introduction ---

Parafocus shooting is a visual exercise about the parabola 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.

Set up Choose a level of difficulty to start your exercise:
Detailed menu for the parameters of this exercise.
Other exercises on:
The most recent version
This page is not in its usual appearance because WIMS is unable to recognize your web browser.
In order to access WIMS services, you need a browser supporting forms. In order to test the browser you are using, please type the word wims here: and press ``Enter''.

Please take note that WIMS pages are interactively generated; they are not ordinary HTML files. They must be used interactively ONLINE. It is useless for you to gather them through a robot program.