Translate the following inference to logic notation: For all x, y_4 will make tea. For all x, y_4 will cook and x_13 will write a letter. Therefore there is at least one x for which y_4 will make tea and y_4 will cook.
forall x: P(x). forall x: Q(x) and R(x). Therefore exists x: P(x) and Q(x).