(i) Consider the class 118 - 126 and 127 - 135 The lower limit of 127 - 135 = 127 The upper limit of 118 - 126 = 126 Half of the difference = 127 -126/2 = 0.5 So, the new class interval formed from 118 - 126 is (118 - 0.5) - (126 + 0.5), i.e., 117.5 - 126.5 Continuing in the same manner, the continuous classes formed are: (i) Yes, frequency polygon. (ii) No, this frequency includes all leaves whose length are from 144.5 mm to 153.5 mm.