Which of the following statements about economic growth is accurate?
a) the world’s sustained economic growth has only been occurring over the last 300 to 400 years.
b) economic growth has been shared equally among all the countries in the world since the start of the most recent generation.
c) countries in africa and south america are responsible for most of the economic growth in the world since the 1600s.
d) sustained economic growth has been occurring since the start of the roman empire.

Suppose that xtel currently is selling at $40 per share. you buy 500 shares using $15,000 of your own money, borrowing the remainder of the purchase price from your broker. the rate on the margin loan is 8%. a. what is the percentage increase in the net worth of your brokerage account if the price of xtel immediately changes to (a) $44; (b) $40; (c) $36? (leave no cells blank - be certain to enter "0" wherever required. negative values should be indicated by a minus sign. round your answers to 2 decimal places.) b. if the maintenance margin is 25%, how low can xtel’s price fall before you get a margin call? (round your answer to 2 decimal places.) c. how would your answer to requirement 2 would change if you had financed the initial purchase with only $10,000 of your own money? (round your answer to 2 decimal places.) d. what is the rate of return on your margined position (assuming again that you invest $15,000 of your own money) if xtel is selling after one year at (a) $44; (b) $40; (c) $36? (negative values should be indicated by a minus sign. round your answers to 2 decimal places.) e. continue to assume that a year has passed. how low can xtel’s price fall before you get a margin call? (round your answer to 2 decimal places.)