Photo credits
Очистка_ртути_перегонкой_в_токе_газа
Purification of mercury by distillation
Spot the difference
An image of two zebras
1024px-Sextante,_Acervo_do_Museu_Paulista_da_USP_(6)
981px-Wikipedia20_Knowledge.svg
https://commons.wikimedia.org/wiki/File:Wikipedia20_Knowledge.svg
1024px-Magnifying_glass_with_focus_on_paper
https://commons.wikimedia.org/wiki/File:Magnifying_glass_with_focus_on_paper.png
512px-African_Bush_Elephant
https://commons.wikimedia.org/wiki/File:African_Bush_Elephant.jpg
1024px-Piata_Romana_-_Iarna
https://commons.wikimedia.org/wiki/File:Piata_Romana_-_Iarna.jpg
Tin Robot
https://commons.wikimedia.org/wiki/File:Unknown_Chinese_Maker_Tin_Wind_Up_Radar_Robot_Front.jpg
1200px-Emna_Mizouni_'I_edit_Wikipedia'_heart_t-shirt_07-2015
https://upload.wikimedia.org/wikipedia/commons/a/a3/Emna_Mizouni_%27I_edit_Wikipedia%27_heart_t-shirt_07-2015.jpg