4. To determine the standard working time for a special job, following observation data is collected. Observation 1 2 3 4 5 6 7 8 Times 17 18 15 14 13 15 16 13 a) If the person observed worked at a pace that is 80 percent of normal, what should be the normal time for this task? If the person observed worked at a pace that is 20 percent faster than average, what should be the normal time for this task? b) If the person observed worked at a pace that is 80 percent of normal, and if the appropriate allowance for this task is 25 percent of job time, what should be the standard time? c) How many observations would be needed to be 95% confident that the maximum error in the observed time is 1