If the radius of atom is 4 × 10^-3 nm (Nano meter), so its diameter is: * 8 × 10^-12 m
8 × 10^-3 µm
8 × 10^-6 km
8 × 10^-9 cm

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.