The widget industry has the following characteristics: over 600 producers with no one producer furnishing more than 0.5% of the industry’s total output; widgets produced by different firms are identical and there are no brands or labels on the product; there are no significant barriers to entry to the widget market; there is no economic profit in the long run. The widget market is best described as what type of market? Perfect competition Monopolistic competition Differentiated oligopoly Undifferentiated oligopoly Pure monopoly

Perfect competition

Explanation:

The widget market is best described as a perfectly competitive market. A perfectly competitive market is a type of market without restriction in entry and exit, it is characterized by many sellers of similar products and buyers and there is perfect information about the price of goods. In a perfectly competitive market, due to the free entry and exit, no single producer has an influence over the price of goods. In the long-run, in perfectly competitive market, there is no economic profit because more producers will enter the market if it is profitable thus bringing about competition which will cause average revenue to equal average cost in the long run.

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.