Final answer:
Tempering is a heat treatment process, and its specific temperature varies with material. For example, hard plastics like polystyrene and poly(methyl methacrylate) have glass transition temperatures around 100°C. The exact temperature for tempering a product is not given and depends on the material.
Step-by-step explanation:
Tempering is a process that involves heating a material to a specific internal temperature to achieve certain properties like hardness or brittleness in metals, or flexibility in polymers. In the context of polymers, the glass transition temperature (Tg) is important, which is the temperature at which a polymer goes from a hard and relatively brittle state into a rubbery or flexible state. For example, hard plastics like polystyrene and poly(methyl methacrylate) have Tg values of about 100°C, indicating they are used while in a rigid state below this temperature. The question does not provide enough specific information to precisely identify the temperature at which a product is tempered, as it depends on the material in question. However, based on the given options and the context that temperatures below 100°C are not usually related to tempering processes for metals or polymers, we can infer that the question is ambiguous, and more details are necessary for an accurate answer.