Measuring specimens of nylon yarn taken from two spinning machines, it was found that 8 specimens from the first machine had a mean denier of 9.67 with a standard deviation of 1.81 , while 10 specimens from the second machine had a mean denier of 7.43 with a standard deviation of 1.48. Assuming that the populations sampled are normal and have the same variance, test the null hypothesis \(\mu_{1}-\mu_{2}=1.5\) against the alternative hypothesis \(\mu_{1}-\mu_{2}>1.5\) at the 0.05 level of significance.