Actually there are two triangles but the 'borderless' one stands out for me loud and clear and the bordered one is underneath it, turned the other way, forming a six point star. The black shapes, disconnected, require more effort for me to see as not being circles supporting the points of the top triangle- but pies with a wedge missing/ pacman shapes and ^ >. It's not automatic to see it like that. But the white triangle is. You?

Could be familiar symbol association. But the white triangle is popping. No question it's there! It's the first thing I noticed. Interested to hear from others.

I can do the hand thing ok, as long as I'm moving my hands.  I don't need to look at them, simply doing the motions works.  I can still figure it out without doing it, but it takes more effort.  The one in the middle, second line just looks like a penis though.  I guess it's a thumb, but I have trouble knowing what it's supposed to represent.  The one above is a bit confusing too.

In the second picture, I see the black shapes and lines first, but I can easily flip flop between them.  Of the 10 questions, I'm fairly right handed.  There is one I would use my left hand for, and 2 that would switch.

As I always thought, I'm mostly right-handed but a little more ambidextrous than most.