According to the information given in Table: Number of interval employeescentres Age (x), years (f), pers. 30-35 10 35-40 40 40-45 80 45-50 100 50-55 20 Total 250 (x) 32.5 37.5 42.5 47.5 52.5 X Calculate the coefficient of variation (use 1 "." separated decimal unit, e.g. 5.5) 700 tourists cross the border daily. 20% mechanical sample was organized. Results show that the average age of tourists is 40 years, age standard deviation is 7 years. With the probability 0.95 (t-1.96), calculate absolute margin of error. In answer use 2 decimal units, do not write units of measure (e.g. 1.23).