It seems that you have missed the necessary details for us to answer this question, so I had to look for it. Anyway, here is the answer. If the US <span>adopted and maintained a policy of minimal control of co2 emissions, the level that we would expect its emissions to be in 2020 is that WE CAN'T TELL FROM THIS DATA. Hope this helps.</span>
The controlled variable is the variable that remains the same throughout the whole experiment. Here, the warm water and the same dishes are the same throughout the whole experiment- so they are the controls
