At the same moment, one rock is thrown upward at 4.5 m/s and another thrown downward at 3.4 m/s. What is the relative velocity of the first rock from…

At the same moment, one rock is thrown upward at 4.5 m/s and another thrown downward at 3.4 m/s. What is the relative velocity of the first rock from the perspective of the second rock? Assume that up is positive.