How to use a graphic flight computer to find ground speed and true heading<br>Align the wind direction under the " true index " mark by rotating the azimuth plate. If the winds are from 330 ° at 20 knots, align 330 under the true index. Align the grid so the center grommet is over one of the heavy lines.

Based on the paragraph above can we conclude that "To find ground speed using a graphic flight computer you align the grid so the center grommet is over one of the heavy lines."?