Consider the conversion of X to Z through the sole intermediate Y. Given the reaction-energy diagram shown below, which step is the rate-limiting step? Explain your reasoning. 
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A never-used, latest model of the iPhone X, produced by Apple, featuring advanced technology and features, as of its release.
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Having the duty to deal with something or having control over someone, often implying the ability to make important decisions or obligations.
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An individual responsible for directing and overseeing the activities and operations of a group or organization.
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