A psychology professor wants to know whether confidence in memory skills is related to memory quality in current first-year students at his small college. Participants in the study (first-year students at his college) complete an online memory task. The students are first shown a list of 60 words. Next they are shown a list of five new words that are completely unrelated to words on the original list. Then they are asked to identify the words on the second list that appeared on the original list. He uses the percentage of new unrelated words that were mistakenly thought to be on the original list as his measure of memory quality. He also asks the students to report several characteristics such as their age, their gender, and a self-assessment of their memory skills. Each of the 750 first-year students (338 males and 412 females) at his school volunteers to participate. The professor chose 75 students at random to complete the memory task and answer the questions. The average percentage of new unrelated words that were mistakenly thought to be on the original list was 12%. The professor infers that if all 750 first-year students had completed the study, the results would show that an average of 12% (plus or minus sampling error) of new words were mistakenly identified as original words despite being completely unrelated to the words on the original list.1.Which of the following are variables in the study? Check all that apply. a. The students' percentage of new unrelated words that were mistakenly thought to be on the original listb. The students' self-assessment of their memory skillsc. The 750 studentsd. The 75 students 2. What is the population in the study?a. The 12% of new words mistakenly identified as original words despite being completely unrelated to words on the original listb. The 750 first-year students at the college c. The 75 students who participated in the study