ImageBlock Module- Responsive/Fluid images
Figured it out. In order to make a image that is a part of a imageblock, responsive/fluid, you need to:

1.) Use firebug to find the image block class for the imageblock.
2.) For me I added this to CSS  

#block-imageblock-### .imageblock-image{
    width:100%;


}


This will make your image that you've uploaded into a ImageBlock responsive/fluid to any screen resolution