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The format of the GARCH equation is σ²_n = ω + αμ²_n-1 + βσ²_n-1, where (α + β) = persistence. For a model to be stationary over time, the persistence must be less than one. A persistence of one means there is no mean reversion and the higher the persistence (given that it is less than one), the longer it will take for volatility to revert to a long run mean level following a large shock or movement. The persistence for Equation 2 is (0.04 + 0.95) = 0.99, which is less than one meaning there is mean reversion. The persistence for Equation 1 is higher than that of Equation 3, meaning mean reversion will take longer for Equation 1. Because the persistence for Equation 1 is less than one, Equation 1 is a stationary model. Equation 3 has a persistence greater than one, which mean the model shows no mean reversion. Only Statement I is correct.