Which of the following statements is true about marginal revenue?
a) if marginal revenue is zero, it means that quantity demanded falls to zero when a firm changes its price.
b) if marginal revenue is negative, the additional revenue received from selling 1 more unit of the good is smaller than the revenue lost from receiving a lower price on all the units that could have been sold at the original price.
c) if marginal revenue is positive, the additional revenue received from selling 1 more unit of the good is smaller than the revenue lost from receiving a lower price on all the units that could have been sold at the original price.
d) marginal revenue increases as price falls and quantity sold increases.

In a macroeconomic context, what are implicit liabilities? money owed to people possessing government issued bonds. the amount of money that firms collectively owe to shareholders. money that the government has promised to pay in the future. payments that the federal government undertakes only during periods of recession. which of the choices is a significant implicit liability in the united states? military spending education spending national science foundation spending social security

Richardson hired j. c. flood company, a plumbing contractor, to correct a stoppage in the sewer line of her house. the plumbing company's 'snake' device, used to clear the line leading to the main sewer, became caught in the underground line. to release it, the company excavated a portion of the sewer line in richardson's backyard. in the process, the company discovered numerous leaks in a rusty, defective water pipe that ran parallel with the sewer line. to meet public regulations, the water pipe, of a type no longer approved for such service, had to be replaced either then or later, when the yard would have to be excavated again. the plumbing company proceeded to repair the water pipe. though richardson inspected the company's work daily and did not express any objection to the extra work involved in replacing the water pipe, she refused to pay any part of the total bill after the company completed the entire operation. j. c. flood company then sued richardson for the costs of labor and material it had furnished. (c) for what, if anything, should richardson be liable? explain."

Amajor advantage of case studies is