1- A work sampling study is to be performed on an INSURANCE OFFICE XYZ staff consisting of 30 persons to see how much time they spend processing claims. The duration of the study is 25 days, eight hours per day. Processing claims is only one of the activities done by the staff members. The office manager estimates that the proportion of time processing claims - 0,40. Hence, At the 95 percent confidence level, how many observations are required if the upper and lower confidence limits are 0.35 and 0.45? a) 9 369 b) 678 C) 468 d) 185 740