Suppose, at a given point in time, Sally's Smoothie Shack operates in a perfectly competitive market and is producing its profit-maximizing level of output. Suppose further that at this level of production its average fixed cost of producing a smoothie is $1.30, average variable cost is $2.50, and marginal cost is $3.60. At this moment Sally is earning economic profits. Over time, everything else held constant, the number of firms selling smoothies will .

The stock of grommet corporation, a u.s. company, is publicly traded, with no single shareholder owning more than 5 percent of its outstanding stock. grommet owns 95 percent of the outstanding stock of staple inc., also a u.s. company. staple owns 100 percent of the outstanding stock of clip corporation, a canadian company. grommet and clip each own 50 percent of the outstanding stock of fastener inc., a u.s. company. grommet and staple each own 50 percent of the outstanding stock of binder corporation, a u.s. company. which of these corporations form an affiliated group eligible to file a consolidated tax return?