A group of 50 students were asked to estimate the length of a line to the nearest mm. Their results, arranged in order of size, are given in Table 14.9. estimations (mm) 67 69 69 71 71 72 73 74 75 75 76 76 76 77 77 77 77 78 78 79 79 79 79 80 80 80 81 81 81 81 81 83 83 83 83 84 84 85 85 85 86 86 86 87 89 90 91 91 92 94 Table 14.9 Make a frequency distribution table, taking six equal intervals 65-69, 70-74, 75-79,..., 90-94. a What is the modal class of the distribution? b What is the median estimate? c What is the median class?​