Several Questions

1.
You are interpreting the results of an opinion poll.  In a random sample of 100 small business owners, you find that of the 40 large business owners, a total of 30 support a proposal to implement a local sales tax.  Of the 60 small business owners, 20 support it.  How can you determine if there is a relationship between size of business owned and whether the owner is likely to support a sales tax?

2.
You are a training manager for a manufacturing firm and have three new training programs to assess.  You assign, at random, equal numbers of employees to each of the training programs in order to determine which program is most efficient.  How might you go about analyzing the results?

3.
Here's a link to a report by the San Francisco Department of Public Health that suggests criminals are more likely to own a gun than non-criminals:  http://www.dph.sf.ca.us/Reports/Firearms/Part7Criminal.pdf  What does this suggest to you?

4.
A senior accounting major at Midsouth State University has job offers from four CPA firms.  To explore the offers further, she asked a sample of recent trainees how many months each worked for the firm before receiving a raise in salary.  The sample information is:

Number of months before first raise in salary

CPA Inc.        AB Int.                    Acct. Ltd.              Pfisters

12                 14                           18                         12

10                 12                           12                         14

14                 10                           16                         16

12                10

At the .05 level of significance, is there a difference in the mean number of months before a raise was granted among the four firms?