The following table gives the distribution of the lengths of 100 iron rods Length (cm) 40-44 45-49 50-54 55-59 60-64 65-69 70-74 Frequency 6 12 22 30 15 10 5 a) Estimate the median rod length by i) Using the linear interpolation method. ii) A cumulative frequency curve. b) Estimate the modal rod length by i) using a histogram. ii) Using the interpolation method