Estimate annual market demand and annual market potential in the US for a toothbrush with an inbuilt digital calendar that shows daily appointments while users are brushing.

Assume that the buyer is an individual and that each individual can buy and use more than one such calendar toothbrush a year. Clearly list and justify all other assumptions; e.g., market/tms, no. of buyers, no. of units purchased by average buyer, and price.