Final answer:
Due to missing information in the question, it is not possible to provide an exact quantity supplied of watches at a price of $0. Generally, the quantity supplied would be very low or zero at that price, as suppliers lack the incentive to provide goods without profit.
Step-by-step explanation:
The question seems to be about understanding the relationship between price and quantity supplied in the context of economics, termed as the supply function. However, it appears there is missing information or an incorrect reference to personal pizzas in the provided details that does not align with the actual question about the supply of watches. Assuming we have a general form of the supply function for watches, the question 'Find the quantity supplied at a price of $0' asks for the calculation of how many watches (in hundreds) would be supplied in the market if the price of the watches is set to $0.
Without the specific supply function for watches, we can't calculate an exact quantity. Generally, in economics, if the price of a good is $0, the quantity supplied would also be very low or zero, because suppliers would not have an incentive to supply the product without a profit. However, this depends on the actual supply function which is not provided here.