Use the following Phillips curve equation to answer this question: ?t - ?t-1 = (m + z) - ?ut. Which of the following will cause an increase in the natural rate of unemployment?

In the 1930s the United States charged an average tariff rate

A) that cut its exports to other countries by 50 percent. B) that exceeded 50 percent. C) that was less than its average tariff rate in 2007. D) that was less than 2 percent.

In the 1970s, the relationship between stock-market prices and the consumer price index was roughly equal to that of the 1920s, rising in roughly equal amounts

Indicate whether the statement is true or false