Researchers are trying to determine if there is a difference in the average lifespan of two species of fruit fly: Ceratitis capitata and Drosophila melanogaster. They measure the lifespans of two random samples of each species. The SRS of Ceratitis capitata was of size 105 and had an average lifespan of 51 days with a standard deviation of 7 days. The SRS of Drosophila melanogaster was of size 95 and had an average lifespan of 48 days with a standard deviation of 6 days. Let ₁ denote the mean lifespan of Ceratitis capitata and μ2 denote the mean lifespan of Drosophila melanogaster. Provide an estimate for the difference in the mean lifetimes of these two species.