Have there been studies on this?, page-3

  1. 12,742 Posts.
    lightbulb Created with Sketch. 39
    Found this.
    https://hotcopper.com.au/data/attachments/6233/6233070-3c9033321091c76ee2a799ac5e3d142b.jpg
    https://hotcopper.com.au/data/attachments/6233/6233071-b9944fbd9e1dd6762eb287e13cc41807.jpg

 
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