Why isn't the combination of consumer and producer surplus maximized if there is either excess demand or supply?

Which of the following is one of the advantages primarily associated with a performance appraisal? (a) it protects employees against discrimination on the basis of race. (b) it motivates employees to work on their shortcomings. (c) it encourages employees to play the role of the whistle-blower. (d) it accurately measures the resources of the firm.

Sales at a fast-food restaurant average $6,000 per day. the restaurant decided to introduce an advertising campaign to increase daily sales. to determine the effectiveness of the advertising campaign, a sample of 49 days of sales were taken. they found that the average daily sales were $6,300 per day. from past history, the restaurant knew that its population standard deviation is about $1,000. if the level of significance is 0.01, have sales increased as a result of the advertising campaign? multiple choicea)fail to reject the null hypothesis.b)reject the null hypothesis and conclude the mean is higher than $6,000 per day.c)reject the null hypothesis and conclude the mean is lower than $6,000 per day.d)reject the null hypothesis and conclude that the mean is equal to $6,000 per day.expert answer

David paid $975,000 for two beachfront lots in coastal south carolina, with the intention of building residential homes on each. two years later, the south carolina legislature passed the beachfront management act, barring any further development of the coast, including david's lots. when david files a complaint to seek compensation for his property, south carolina refuses, pointing to a passage in david's own complaint that states "the beachfront management act [was] properly and validly designed to south carolina's " is south carolina required to compensate david under the takings clause?