X Canvas D Question 4 (20 marks) (a) A census of purchasing agents from industrial companies found that 25% of the buyers reported lower levels of new orders in February of 2020 than in earlier months. What is the probability that the sample proportion will be within 0.01 of the population proportion if the sample size is 160? (7 marks) (b) Student Union at the local university sampled 60 textbooks at the University Bookstore and determined that of these 60 textbooks, 60% had been marked up in price more than 50% over wholesale cost. (i) Construct a 92% confidence interval for the proportion of books marked up more than 50% by the University Bookstore. (8 marks) (ii) The University Bookstore claimed that the proportion of books marked up more than 50% is 70%. With 0.08 significance level, can you test the University Bookstore's claim only based on the result in (i)? Why and how? (5 marks) D Question 5 (20 marks) Sample data on weights of babies and their foot lengths are recorded as follows: HOMI