AlphaMartsells groceries at the west end of Main Street, a street that is one kilometre long. AlphaMartcompetes with BetaMarket, which is locatedat the east end of the street. AlphaMart and BetaMarketsell groceriesthat are identical in every respect, apart from the locations of the two stores. The marginal cost of an item of groceries is $3 to both retailers.

Main Street is home to 200consumers; the consumers are evenly spaced along the street. Each consumer demands one itemof groceries, and faces a travel cost of $12 per kilometre.

How many items of groceries does BetaMarket sell in Equilibrium?