In situations involving two or more variables, both histograms ...

[tichca]

In situations involving two or more variables, both histograms and bar charts can be used for multiple variables on the same graph.
 
  Indicate whether the statement is true or false

Question 2

A cell phone service provider has selected a random sample of 20 of its customers in an effort to estimate the mean number of minutes used per day.
 
  The results of the sample included a sample mean of 34.5 minutes and a sample standard deviation equal to 11.5 minutes. Based on this information, and using a 95 percent confidence level:
  A) the critical value is z = 1.96
  B) the critical value is z = 1.645
  C) the critical value is t = 2.093
  D) The critical value can't be determined without knowing the margin of error.

[sylvia]

Answer to Question 1

FALSE

Answer to Question 2

C