Hey family takes a car trip and they travel from an hour at 80 km/h and than for 2hourse at 40 km/h finf the average speed during the trip

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

Iwill give brainliest if you answer right : )

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