How to change the image of Biology please？

International board Development
#1

I want to change the image of Biology.
I search the hero3 folder, it seems the image is encoded.
Does anyone know how to change image resource please?
Or tell the where the image resource located in hero3 please?

#2

heroescommunity.com/viewthread.php3?TID=39961

There you can probably find some information.