Three students independently measure the arm span of a participant and calculate their height using an equation. Their results are 165cm, 169cm and 170cm. They then measure the participant's height and their results are 166cm, 168cm and 167cm. Answer the following questions (2 marks) (a) Are these two measures indirect or direct measures of height? (b) Are these measures objective or subjective? (c) Give 2 reasons why the results may vary between the three students