Genetic engineering for cancer treatment. Here's a new idea for treating advanced melanoma, the most serious kind of skin cancer: genetically engineer white blood cells to better recognize and destroy cancer cells, then infuse these cells into patients. The subjects in a small initial study were 11 patients whose melanoma had not responded to existing treatments. One question was how rapidly the new cells would multiply after infusion, as measured by the doubling time in days. Here are the doubling times: 25 1.4 1.0 1.3 1.0 1.3 2.0 0.6 0.8 0.7 0.9 1.9 (a) Examine the data. Is it reasonable to use the t procedures? (b) Give a 90% confidence interval for the mean doubling time. Are you willing to use this interval to make an inference about the mean doubling time in a population of similar patients? Explain your reasoning.