Ateacher is experimenting with a new computer-based instruction and conducts a study to test its effectiveness. in which situation could the teacher use the two-sample t-test for comparing two population means? the teacher uses a combination of traditional methods and computer-based instruction. she asks students which they liked better. she wants to determine if the majority prefer the computer-based instruction. the teacher randomly divides the class into two groups. one of the groups receives computer-based instruction and the other group receives traditional instruction without computers. after instruction, each student takes a test and the teacher wants to compare the test scores of the two groups. the teacher gives each student in the class a pretest. then she teaches a lesson using a computer program. afterwards, she gives each student a post-test. the teacher wants to compare test scores for each student to see whether the data will show an improvement.