Optical illusion

Can you see the three faces?

source : http://www.optillusions.com/dp/1-4.htm
















What do you see below?
A lady or a musician? See both?














source : http://www.eyetricks.com/0107.htm

Try to count the number of black dots on the image below...
















source :http://www.eyetricks.com/0107.htm



Are the lines below straight or are they curved? source : http://www.eyetricks.com/0107.htm