page 10 11. A field trial was carried out to investigate the effect of mass of phosphate fertiliser applied on the growth of barley. The barley was planted in plots of equal area on a hillside and fertiliser applied as shown in the diagram. 2 g/m2 2 g/m2 2 g/m2 4 g/m2 4 g/m2 4 g/m2 6 g/m2 6 g/m2 6 g/m2 Which of the following procedures would improve the field trial design to take into account higher soil moisture levels at the bottom of the hill? A Increase the range of phosphate fertiliser masses applied. B Randomise the treatment plots. C Increase the number of plots. D Select another hillside. 12. Which of the following is an example of kin selection? A Worker leafcutter ants raising young ants in their colony. B A vampire bat regurgitating blood to feed an unrelated bat. C A dominant lion feeding on a zebra kill before its offspring. D A young orangutan spending a long period in parental care to learn complex social behaviours. 13. An experiment was carried out to investigate the growth rate of pigs. They were put into five groups of eight pigs, each with the same average initial body mass. Each group was fed a diet which contained either 0, 10%, 20%, 30% or 40% faba beans. The pigs were re-weighed each day for 40 days. Which aspect of the experimental design increased reliability of the results? A Five groups of pigs were used. B The pigs were re-weighed each day for 40 days. C Each group had the same average initial body mass. D Each group contained eight pigs.