Assume there are no investment projects that will produce an expected rate of return of 8 percent or more. There are, however, $2 billion worth of investment projects with an expected rate of return at 7 percent, and an additional $2 billion for every drop of the interest rate by 1 percent. If the real interest rate is 3 percent in this economy, the cumulative amount of investment at the 3 percent or higher rate of return is: a. $10 billion
b. $8 billion
c. $6 billion
d. $4 billion

5. understanding marginal and average tax rates consider the economy of citronia, where citizens consume only oranges. assume that oranges are priced at $1 each. the government has devised the following tax plans: plan a • consumption up to 1,000 oranges is taxed at 50%. • consumption higher than 1,000 oranges is taxed at 20%. plan b • consumption up to 2,000 oranges is taxed at 15%. • consumption higher than 2,000 oranges is taxed at 60%. use the plan a and plan b tax schemes to complete the following table by deriving the marginal and average tax rates under each tax plan at the consumption levels of 300 oranges, 1,200 oranges, and 3,000 oranges, respectively. consumption level plan a plan b (quantity of oranges) marginal tax rate average tax rate marginal tax rate average tax rate (percent) (percent) (percent) (percent) 300 1,200 3,000 complete the following table by indicating whether each plan is a progressive tax system, a proportional tax system, or a regressive tax system. progressive proportional regressive plan a plan b