The context of the following conversation is Carson took the shadow for the substance as part of the substance, making it look bigger.:
Carson says I think I figured it out..
The friend responds That's a good try Carson but you got one thing wrong. Can you guess what it is?.
Carson responds No. Delilah you were always so good at chemistry. Far better than I am..
The friend responds I've had years of study Carson. So anyway you mistook the shadow of the compound substance for the substance itself which led to a disproportionate size..
Carson responds Oh. Good catch Delilah..
The friend responds Yes. I think that one fixup is all we need to get an A..