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Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

Asap! how do you lengthen a pattern piece? (family and consumer science, sewing)

In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?