Translate the following inference to logic notation: If Susan were a musician, then Sarah is cooking. For all x, z is a musician if and only if z will write a letter. Susan is writing a letter or it is snowing. If it snows, then Sarah is cooking. Therefore Sarah is cooking.
P(a) -> p. forall x: P(x) <-> Q(x). Q(a) or q. q -> p. Therefore p.