Container puzzles

While I worked at the port, I'd send around a puzzle every Friday. Something to talk about in the kitchen.

This one is about weighing shipping containers. I blatantly stole the idea for this puzzle from the mathematician Paul Salomon.

Anyhow, try them. They’re fun. Kids would be good at them too.  For each of the six questions, you have to rank the coloured containers from heaviest to lightest.  The results will be different for each puzzle.  For example, it's not the case that green is always the heaviest.

Assume that if the colour is the same then the weight is the same, and that the fulcrum of the scale is always in the middle.