1.7.1 Multiple Moves
If an action allows units to make multiple moves, take each move one after the other, following the rules that follow for each move (i.e., don’t simply add the movement distances together). For example, a Space Marine Tactical detachment (Speed 15cms) taking a March action would make three moves of 15cm each, rather than one move of 45cms.

1.8.1 Dangerous Terrain Test
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Units may choose to move through dangerous terrain cautiously. A unit that is moving cautiously counts as having a speed of 5cm, but is allowed to re-roll any Dangerous Terrain tests that it fails.