If real consumption spending increases by $400 billion each time real disposable income rises by $1,000 billion, the marginal propensity to consume is

The above figure shows the market for steel ingots. If the market is competitive, and the government institutes a $100 specific tax on steel, then

A) less than the socially optimal quantity of steel is produced. B) the socially optimal quantity of steel of 50 units is produced. C) the socially optimal quantity of steel of 100 units is produced. D) more than the socially optimal quantity of steel is produced.

Modern economists are increasingly using microeconomic analysis in macroeconomics because

A) microeconomic theory is more scientific. B) aggregate outcomes stem from decisions made by individuals, business firms and government. C) macroeconomic subjects such as inflation affect all individuals. D) macroeconomics is older and more outdated.