Agar cubes can be used to demonstrate the effect of changing surface area to volume ratio on diffusion. Three different agar cubes made using a dilute acid were placed into an indicator solution that diffused into the cubes. When the indicator came into contact with the acid it changed colour. The cubes were 1cm³, 2cm³ and 3cm³ and were left in the indicator solution for 10 minutes. All other variables were kept the same. The results for the 2 cm³ cube are shown. Which diagrams represent the results for the 1 cm³ and the 3cm³ cubes?

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