4. A consumer group has determined that the distribution of life spans for gas ranges (stoves) has a mean of 15.0 years and a standard deviation of 4.2 years. The distribution of life spans for electric ranges has a mean of 13.4 years and a standard deviation of 3.7 years. Both distributions are moderately skewed to the right. Suppose we take a simple random sample of 35 gas ranges and a second SRS of 40 electric ranges. Which of the following best describes the sampling distribution of f5 f; , the difference in mean life span of gas ranges and electric ranges? A. Mean = 1.6 years, standard deviation = 7.9 years, shape: moderately rightskewed. B. Mean = 1.6 years, standard deviation = 0.92 years, shape: approximately Normal. C. Mean = 1.6 years, standard deviation = 0.92 years, shape: moderately right skewed. D. Mean = 1.6 years, standard deviation = 0.40 years, shape: approximately Normal. E. Mean = 1.6 vears. standard deviation = 0.40 vears. shape: moderatelv right skewed