5 2. A truck took 4 hours to complete a journey. At the first 2h,
it travelled at an average speed of 70 km/h. For the rest of
the journey, it travelled at an average speed of 80 km/h.
What was the total distance of the journey?

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve