One of the students in the introductory statistics class in exercise 7 claims to have tossed her coin 200 times and found only 42% heads. what do you think of this claim? explain.

For 200 flips, the sampling distribution model is Normal with mean(sub p-hat)=p=0.5;
sigma(sub p-hat)=(root)pq/n
=0.0354
Her sample proportion of p-hat=42% = 0.42
which is about 2.26 standard deviations below the expected proportion,
which is unusual, but not extraordinary.
According to the Normal model, we expect sample proportions this low or lower about 1.2% of the time.

The third one is true. 0.3 > 0.20

The business cycle is the periodic but irregular up-and-down movement in economic activity, measured by fluctuations in real gross domestic product (gdp) and other macroeconomic variables. a business cycle is typically characterized by four phases—recession, recovery, growth, and decline—that repeat themselves over time. economists note, however, that complete business cycles vary in length. the duration of business cycles can be anywhere from about two to twelve years, with most cycles averaging six years in length. some business analysts use the business cycle model and terminology to study and explain fluctuations in business inventory and other individual elements of corporate operations. but the term "business cycle" is still primarily associated with larger (industry-wide, regional, national, or even international) business trends.