What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: Mary is drinking water if and only if it is snowing. For all x_10, x_10 will not drink water. It is snowing or Elisabeth is playing squash.
If Mary drinks water, then it is snowing can be inferred via the biconditional elimination rule. If it snows, then Mary is drinking water can be inferred via the biconditional elimination rule.