I would think conductor since it absorbs heat and which is radiation but that's not the question and the heat it absorbs it touches the food which is conduction
The tray is a radiator, b/c it helps the heat transfer/spread throughout the oven while baking something for example. Unlike a conductor, having energy pass through the tray too quickly barely getting any heat directly around the tray. And an Insulator preventing the heat from getting through the metal baking tray at all.
Explanation: If three potatoes have mass of 667 g that means that each potato weighs 667/3= 222.33 g (approx) so 100 potatoes must be 100*222.33= 22233 g which equals 22.2 kg because 1 g=1000 kg
