A recent article in The Wall Street Journal compared the cost of adopting children from China with that of Russia. For a sample of 16 adoptions from China the mean cost was $11,045 with a standard deviation of $835. For a sample of 18 adoptions from Russia the mean cost was $12,840 with a standard deviation of $1,545. Assume the two population standard deviations are not the same.
(1) Find the degrees of freedom for unequal variance test. (Round down your answer to the nearest whole number.)
(2) State the decision rule for .05 significance level: H0: μc ≥ μr ; H1: μc < μr. (Negative amount should be indicated by a minus sign. Round your answer to 3 decimal places.)
(3) Compute the value of the test statistic. (Negative amount should be indicated by a minus sign. Round your answer to 3 decimal places.)