Acollege newspaper reporter is investigating textbook availability at online retailers. He decides to investigate one texmook for each of the following ? subjects: calculus, biology, chemistry, physics, statistics, geology, and general engineering. He consults textbook industry sales data and selects the most popular nationally used textbook in each of these subjects. He visits websites for a random sample of major online texmook sellers and looks up each of these I" textbooks to see ifthey are available in stock for quick delivery through these retailers. Etased on his investigation, he writes an article in which he draws conclusions about the overall availability of all college textbooks through online textbook retailers. Is his sample representative of the population of all college textbooks? C) No, he should have looked up every book for every subject O Yes, he selected books from 7' different subjects (:3 No, he only sampled ? subjects and only one book from each subject C) Yes, he visits random online retailers to check prices A college newspaper reporter is investigating textbook availability at online retailers. He decides to investigate one texmook for each of the following ? subjects: calculus, biology, chemistry, physics, statistics, geology, and general engineering. He consults textbook industry sales data and selects the most popular nationally used textbook in each of these subjects. He visits websites for a random sample of major online texmook sellers and looks up each of these I" textbooks to see ifthey are available in stock for quick delivery through these retailers. Etased on his investigation, he writes an article in which he draws conclusions about the overall availability of all college textbooks through online textbook retailers. Which of the following describe some possible sources of bias in this study? C] He only looked at the most popular textbook in each of the subjects C] The 7" subjects that he investigated are all in mathematics and the sciences C] The textbooks he investigated were all used Cl He only looked up online prices