Which of these actions would increase the rate of this reaction? Check all that apply.

A more concentrated HCl solution has more acid particles in a given volume, so it causes more frequent effective collisions with the CaCO₃. Crushing the CaCO₃ into a fine powder increases its exposed surface area, allowing more of it to react at once. Increasing pressure generally speeds reactions involving gaseous reactants; this reaction uses a solid and an aqueous solution, so pressure would not increase its rate.

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