donald verrilli: that's correct. justice breyer: -- where can you point me in the record where this was made by the agency? it is a very important principle of administrative law that we will only uphold the rule based on arguments that were considered by the agency. it is not something i recall. donald verrilli: you are exactly right in stating in principle, our argument in this case is that this question here is under and one a, -- n1a, says that epa shall regulate under this section if he determine that such regulation is appropriate and necessary. therefore when ep makes a judgment to regulate under this, it is appropriate and necessary. justice scalia: well you're just seeing the argument is right. the agency must have arrested its decision. donald verrilli: i think that the agency in the order of being challenged here did use the approach. but beyond that it would be one thing if this were a case in which you had a situation that epa faced a situation where 50% or 75% were going to raise -- face vastly economic