Two samples of size 25 and 35 are independently drawn from two normal populations where the unknown population variances are assumed to be equal. The number of degrees of freedom of the equal-variances t test statistic is: A. 60 B. 58 C. 35 D. 59 If some natural relationship exists between each pair of observations that provides a logical reason to compare the first observation of sample 1 with the first observation of sample 2, the second observation of sample 1 with the second observation of sample 2, and so on, then the samples are referred to as: A. matched samples B. random samples C. independent samples D. weighted samples