The "SRC=" part of an IMG tag tells where to get the image from. For the graphics here, the SRC is "../img/mix1.gif". However, if you were to upload it to GeoCities, this would cause the browser to look for it at "http://www.geocities.com/your_space/img/mix1.gif", and it may not be there. So, if you put it on your page, the SRC will need to be changed. If the page and graphic are in the same subdirectory (folder), it would say:
SRC="mix1.gif"
Or, if the page were in the 4436/toys directory, and the graphic was in the 4436/pics directory, it would say:
SRC="../pics/mix1.gif"
"../" means "look in the directory above this one".