A store has five shelves and average weekly sale is Tk. 30000. Shelf 1 accounted for 1/4 of the store's average weekly sales and shelves 2 and 3 each accounted for 2/3 as much as shelf 1. The shelf 4 alone accounted for as much as shelf 1, then which of the following could have been the average weekly sales of shelf 5 for the store?