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The central carbon of the tert-butyl carbocation, (CH3)3C+, is

Which of the following is isobutyl alcohol?

Which of the following is NOT an assumption or condition that needs to be checked for a paired t​-​interval?

Suppose the​ P-value is 0.1039 at α equals=0.05. Make a conclusion.

Speeds of cars were measured as they passed one point on a road to study whether traffic speed controls were needed.​ Here’s a histogram and boxplot of the measured speeds. Accurate statements about this distribution include which of the following: I. The distribution is fairly symmetric. II. The distribution is right skewed with a large outlier. III. A normal probability plot would add information about the normality of the data set.

A survey of investors finds that​ 60% use a full service brokerage firm to invest in​ stocks, 30% trade stocks online and​ 24% do both. What is the probability that an investor selected at random uses a full service brokerage firm or trades stocks​ online?

Which of the following is not an assumption​ and/or condition required for constructing a confidence interval for the​ proportion?

A researcher is conducting a study on Internet use. He decides to first categorize the population by education level​ (high school, college​ graduate, advanced​ degree, etc.) and then survey a select number from each category. What is this sampling strategy​ called?

A researcher is conducting a study on eating disorders. Using a list of recent participants in the online Weight Watchers​ program, she randomly selects a sample from the alphabetized list. What does this list​ represent?  

Suncast Cable offers high definition​ (HD) cable​ TV, Internet and phone services to its customers. For those service issues that can be resolved by calling its technical support​ center, Suncast’s goal is to have the problem solved within 30 minutes. In order to determine how well it is achieving this​ goal, they monitored calls to its technical support center over the last three months. The data compiled is shown in the table below. What is the probability that a call to the technical support center involved an issue with Internet service or was not resolved within 30​ minutes? Problem Resolved? HD cable TV Internet Phone Yes 123 350 77 No 115 122 63