A college professor wants to survey a sample of students taking his course. Here are some details about his course:He teaches555 sections of the course. There are250250250 total students across those sections. There are505050 graduate students and200200200 undergraduate students taking the course. Each section has about505050 students (some graduate and some undergraduate).The professor wants to take a sample of303030 students for a survey. He suspects that opinions on the survey may differ the most based on student type (graduate or undergraduate), so he wants to design his sample to take that into account.