2. A survey was conducted to determine the salaries of employees in thousand Kenyan Shillings in a certain organization. The results of the survey were as follows: Salary ('000 Kshs.) 30-40 40-50 50-60 60-70 70-80 80-90 90-100 100-110 Number of Workers 20 30 60 75 115 100 60 40 (a) Calculate the first quartile (Q1) and third quartile (Q3) hence find the semi-interquartile range of the salaries. (b) Compute the: (i) Median (ii) Standard deviation (iii) Karl-Pearson's coefficient of skewness and interpret your results. (iv) Coefficient of Kurtosis and interpret your results. (v) Pso and Poo, the 80th and 90th percentiles. (c) Draw a cumulative frequency curve using the 'less than' method hence find the number of employees earning between 55 and 85 thousand Kenyan Shillings. (d) Draw a histogram to represent the data given. From it, estimate the modal salary and hence compute the percentage error observed from this estimation process