i)Is the value r = 0.30 significant showing that is positive for the sample of 60 data points at 5% level of significance

ii)A study of the number of business lunches that executives in the insurance and banking industries claim as deductible expenses per month was based on random samples and yielded the following results:

n₁ = 15 x₁ = 9.1 with variance = 2.6

n₂ = 25 x₂ = 8.0 with variance = 4.3.

Test the hypothesis that there is no difference between the averages at 1% significance level.

iii)To compare customer satisfaction levels of two competing cable television companies, 174 customers of company 1 and 355 customers of company 2 were randomly selected and were asked to rate their cable companies. The results are summarized as follows

Company 1

Company 2

Mean

3.51

3.52

Variance

0.26

0.27

Test the hypothesis that company 1 has the better customer satisfaction levels than the company 2 at 5% level of significance.