Students were investigating the effects of a growth hormone placed on the growing tip of a maize seedling. The hormone was used in two different concentrations and distilled water was used as a control on a third set of seedlings. After three weeks the heights of the plants were measured to the nearest centimetre. They are shown in the table. Draw frequency polygons to represent the data and compare the results. Control Height (cm) Frequency 451 0 46 7 47 11 48 12 49 14 50 14 51 18. 52 12 53 8 54 3 55 1 56 0 20% solution Height (cm) 50 51 Frequency 0 1 52 53 54 55 56 17 57 25 58 20 59 12 60. 61 CRONSPrugnao 0 2 9 9 0 40% solution Height (cm) Frequency 54 0 55 2 56 2 57 2 58 7 59 10 60 11 18 62 18 63 16 64 9. 65 5 66