Which of the following is an example of a good for which the demand is likely to become more elastic over time if price changes dramatically?

Suppose that in 2011, 4 million plasma TVs were purchased at $950 each, while in 2012, 3 million plasma TVs were purchased at $800 each. What might have caused this change?

A) The price of LCD TVs (a substitute for plasma TVs) fell. B) The price of LCD TVs (a substitute for plasma TVs) rose. C) Plasma TV manufacturing technology decreased. D) Plasma TV manufacturing technology increased.

Which of the following is true?

i. A rational choice is made on the margin. ii. Microeconomics is the study of the national economy while macroeconomics is the study of the global economy. iii. Economists try to understand how the economic world works by testing normative statements. A) only i B) i and iii C) only ii D) only iii E) i and ii