13 A group of 24 students did experiments to measure the viscosity of two different mixtures. Their measurements (in millipascal seconds (correct to one dp)) are given for both mixtures. Mixture 1 28.0 28.3 29.8 26.5 32.7 32.3 31.4 31.5 29.5 31.0 31.9 26.3 30.7 32.5 25.5 26.2 25.2 33.1 32.9 28.2 33.0 33.2 25.3 25.9 Mixture 2 27.5 28.7 30.6 30.2 28.8 30.5 29.8 27.7 28.4. 27.1. 30.1 28.6 27.8 27.9 28.1 30.7 29.2 28.9 28.1 26.1 30.3 26.1 28.0 29.6 a Draw an ordered back-to-back stem-and-leaf diagram to organise the data. b Calculate the five number summary for each data set. c Draw parallel box-and-whisker diagrams for the two mixtures and comment on what they show