In the attendee task bar, you will find a hand icon. This is the Raise Hand tool.
To get the presenter’s attention, click the hand. After the hand is clicked an audible and visual alert is sent to the presenter.
For the attendee, the hand is gray and will stay solid gray for 20 seconds and then it automatically resets. However, the attendee may reset it before the 20 seconds expires by simply clicking on the solid gray hand or the presenter may reset it as well.