A cognitive psychologist conducted an experiment to investigate the effects of working memory load on visual search times. Eight participants were required to find a target shape on a computer screen under two conditions: a low-load condition (where the target was surrounded by few distractors) and a high-load condition (where the target was surrounded by many distractors). The search times (in seconds) for each participant under both conditions are shown in Table 1 below.
Table 1: Visual search times (in seconds) under low-load and high-load conditions
| Participant | Low-load condition | High-load condition |
|---|---|---|
| Participant A | 4 | 12 |
| Participant B | 3 | 7 |
| Participant C | 6 | 15 |
| Participant D | 5 | 11 |
| Participant E | 3 | 8 |
| Participant F | 4 | 13 |
| Participant G | 2 | 6 |
| Participant H | 5 | 8 |
| Mean | 4.0 | 10.0 |
Calculate the standard deviation for the high-load condition. Show your working and give your answer to two significant figures.
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