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How many total of carbon atoms are in 4-t-butyl-3-ethylnonane? (Note: No need to write structure formula)  

Which of the following best describes the independent variable in an experiment?

Determine whether each data set is continuous or discrete: The number of freshmen entering a college in a certain year. [one] The temperature of a cup of coffee. [two] The number of points scored in a basketball game.  [three] The average number of points scored per game in a basketball season. [four]

A company has 80 employees whose salaries are summarized below.  What is the mean salary?  Round to the nearest dollar. Score Employees $5,001 – 10,000 17 $10,001 – 15,000 12 $15,001 – 20,000 12 $20,001 – 25,000 15 $25,001 – 30,000 24

A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40. The blood pressure readings were given to the nearest whole number. Approximately what percentage of the people aged 25-40 had a systolic blood pressure reading between 110 and 119 inclusive?

“38% of adults in the United States regularly visit a doctor”. This conclusion was reached by a college student after she had questioned 520 randomly selected members of her college. Why is there an error in her conclusion?

The following frequency distribution shows the length of several observed conversations.       What is the upper class boundary for the range of 10-14? [upper] What is the class width? [width]

A certain chain of retail stores has a mean of 473 customers and a standard deviation of 36.2 customers at each location every day.  One day one of the locations has 512 customers.  How many standard deviations from the mean is that? Round your answer to the nearest hundredth. 

Multiple choice questions on a test each have 4 possible answers, one of which is correct.  Assume that you guess the answers to 3 such questions. Use the multiplication rule to find the probability that the first two guesses are wrong and the third guess is correct.  That is, find P(WWC) where W denotes a wrong answer and C denotes a correct answer.  Round your answer to 4 decimal places. [WWC] On your scratch paper, make a complete list of the different possible arrangements of 2 wrong a 1 correct answer.  What is the probability of each combination?  Round to 4 decimal places. [comb] What is the probability of getting exactly 1 correct answer when 3 guesses are made?  Round to 4 decimal places. [one]

In a sample of 1,047 randomly selected adults, 38% said they did not intend to vote in the next election. How many adults in the survey said they did not intend to vote? [one]   In one of Mendel’s experiments with green and yellow peas, 123 out of 515 peas were yellow. What percentage of the peas were yellow?  Round to the nearest tenth of a percent. [two]%   Last year an airline reported that a specific flight was delayed 47 times. This year they reported a 13% reduction in delays for the same flight.  How many times was the flight late this year? [three]