Penningtons Superstore specializes in plus-size fashions for women. It was considering adding a line of teen plus sizes to its stores. Before doing so, it contracted with a marketing research firm to make sure that the teen plus-size market was a viable one. Decision makers needed the results of its study by September 15 so Penningtons could introduce the line the following March, if the market was viable. The major constraint for research here is ___.