Consider the following premises. forall y: U_2(y) or ~U(y). exists y: U(y) or ~U_2(y). Can we infer exists y: U_2(y) -> U(y) from them? If possible, name the inference rules being used at each step.
We can infer exists y: U_2(y) -> U(y) via the existential rewriting rule. Therefore, the answer is yes.