For ten points, name this market structure named for the fact that, without government interference, the market will eventually have only one supplier.
Graphically, its presence is indicated by a negative first derivative of the average cost curve at the point where average cost intersects the demand curve. It arises in markets which require heavy capital investment but have low variable costs, meaning that the cost per unit continues to go down as the quantity sold rises. Examples include unregulated power and telecommunications concerns, where expenses are concentrated in the initial construction of the network. For ten points, name this market structure named for the fact that, without government interference, the market will eventually have only one supplier.
Graphically, its presence is indicated by a negative first derivative of the average cost curve at the point where average cost intersects the demand curve.
natural monopoly [prompt on monopoly]