State the basic physics principles, laws, or equations that students could use to graphically determine the relationship between the release height of block X and the speed at which the two-block system travels after the blocks collide and stick together.

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in most common fires, oxygen is needed for an oxidation reaction to takes place. the combination of oxygen with any element as fuel can create fire and combustion will occur especially if wood, light materials and other combustible things are combine with oxygen.