An analyst wants to get, crate a simple random sample of 500 stocks from all 10000 stocks traded on the New York Stock Exchange, the American Stock Exchange, and NASDAQ. Which of the following methods is least likely to generate a random sample（）
A. Listing all the stocks traded on all three exchanges in alphabetical order and selecting every. 20th stock.
B. Writing the name of each stock on a piece of paper, putting them in a hat, and drawing out 500 names, one at a time.
C. Using the 500 stocks in the S＆P 500.
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Which of the following statements about sampling errors is FALSE（）
A. Sampling errors are errors due to the wrong sample being selected from the population.
B. Sampling error is the difference between a sample statistic and its corresponding population parameter.
C. Sampling errors will vary from one sample to the next.
A stock priced at $100 has a 70 percent probability of moving up and a 30 percent probability of moving down. If it moves up, it increases by a factor of 1.02. If it moves down, it decreases by a factor of 1/1.02. What is the probability that the stock will be $100 after two successive periods（）
A. 9%.
B. 42%.
C. 21%.
The standard normal distribution is most completely described as a:（）
A. symmetrical distribution with a mean equal to its median.
B. normal distribution with a mean of zero and a standard deviation of one.
C. distribution that exhibits zero skewness and no excess kurtosis.
When is the t- distribution the appropriate distribution to use The t -distribution is the appropriate distribution to use when constructing confidence intervals based on:（）
A. small samples from populations with known variance that are at least approximately normal.
B. large samples from populations with known variance that are nonnormal.
C. small samples from populations with unknown variance that are at least approximately normal.
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