The table above shows the distances to some of the nearest stars to our solar system. which of the following is true? i. light from all three stars reaches earth in equal time. ii. light from all three stars travels at the same speed. iii. of the three stars, sirius is the farthest from earth. iv. barnard's star is closer to earth than sirius is.

Moon effect. some people believe that the moon controls their activities. if the moon moves from being directly on the opposite side of earth from you to being directly overhead, by what percentage does (a) the moon's gravitational pull on you increase and (b) your weight (as measured on a scale) decrease? assume that the earth–moon (center-to-center) distance is 3.82 × 10^8 m, earth's radius is 6.37 × 10^6 m, moon's mass is 7.36 × 10^22 kg, and earth's mass is 5.98 × 10^24 kg.

Which of the following are appropriate acceleration units?

If a hiker that weighs 600 newtons climbs a 50 meter hill, how much gravitational potential energy has the hiker gained?