The african and south american continents are separating at a rate of about 3 cm per year, according to the ideas of plate tectonics. if they are now 5000 km apart and have moved at a constant speed over this time, how long is it since they were in contact?

During the apollo moon missions, astronauts were concerned about the effects of newton's third law of motion when: o a. they ejected waste water, because they were concerned that it would push them off course. o b. they reentered earth's atmosphere, because they were carrying heavy moon rocks. o c. they took off from earth, because a large force was required to generate large acceleration. o d. they detected incoming space debris, because the inertia of the debris could damage their ship.