A study of elementary school children, ages 6 to 11 , finds a high positive correlation between shoe size x and score y on a test of reading comprehension. The observed correlation is most likely due to:

Which of the following accurately describes one way that individual goods differ from public goods? a. people can be excluded from using individual goods if they don't pay. b. all individual goods are normal goods. c. demand for individual goods is always inelastic. d. consumer rivalry results in decreasing marginal utility for individual goods.2b2t

Which of the statements best describes why the aggregate demand curve is downward sloping? an increase in the aggregate price level causes consumer and investment spending to fall, because consumer purchasing power decreases and money demand increases. as the aggregate price level increases, consumer expectations about the future change. as the aggregate price level decreases, the stock of existing physical capital increases. as a good's price increases, holding all else constant, the good's quantity demanded decreases.

You are the manager of a large crude-oil refinery. as part of the refining process, a certain heat exchanger (operated at high temperatures and with abrasive material flowing through it) must be replaced every year. the replacement and downtime cost in the first year is $165 comma 000. this cost is expected to increase due to inflation at a rate of 7% per year for six years (i. e. until the eoy 7), at which time this particular heat exchanger will no longer be needed. if the company's cost of capital is 15% per year, how much could you afford to spend for a higher quality heat exchanger so that these annual replacement and downtime costs could be eliminated?