A group of six students carried out an experiment to determine their reaction times using a ruler. Fig. 1.1 shows the basic procedure used for the experiment. [Figure 1.1] The students worked in pairs. • Student A rested their hand on a bench. • Student B then dropped a ruler from a set height. • Student A had to catch the ruler as quickly as possible. • The distance the ruler had dropped was measured and recorded. • The students calculated their reaction times. The formula for calculating reaction time in seconds is shown in Fig. 1.2. [Figure 1.2] Table 1.1 shows the results for the six students. [Table 1.1] There was some background noise in the classroom when the students carried out their experiment. The students thought that this noise might have affected their reaction times. They decided to modify their original experiment to find out if the presence or absence of background noise affects reaction time. Fig. 1.3 shows some results for a reaction time test that the students found on the internet. [Figure 1.3] Table 1.2 shows some probability values of t. [Table 1.2] Another student, when carrying out the ruler experiment shown in Fig. 1.1, noticed that the more repetitions carried out, the faster the reaction time became. The student decided to carry out a different experiment to investigate the effect of repetition on the accuracy of carrying out a task. Five students, V, W, X, Y and Z were tested. • Each student was given a picture of a star, as shown in Fig. 1.4. • Each student sat at a desk so that the star was only visible in a mirror, as shown in Fig. 1.5. • Each student was asked to draw between the double lines of the star when looking at it only in the mirror. Fig. 1.6 shows a star diagram completed by a student. • The students recorded the number of times their lines went outside the double line of the star. [Figure 1.4] [Figure 1.5] [Figure 1.6] Each student repeated the task nine times on the same day. The results are shown in Table 1.3. [Table 1.3]