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different weight systems in different places freedom from traditional ideas traveling from the earth to the moon the effect of gravitation on weight
Scientists can tell the motion of the earth from the motions of five other planets. A fixed star refers to a star that is always stationary on the sky. Ancient people had scant knowledge about the movement of the stars. All the stars on the sky can be seen all year long.
all of which all of them all that all what
it is too small to have a gravitational pull of its own its pull is so small that we tend to ignore it its pull disappears in the presence of the earth’s gravitation it tends to melt and loses its gravitational pull
it demands too great an effort for us to do so we are too familiar with the way things are to question the ideas we have proved that those ideas are correct we are so sure of ourselves that we never doubt anything on the earth
it is fixed if it is outside the earth’s gravitational pull it decreases four times when it is 4,000 miles from the earth’s center it varies with the change of the gravitational attraction between two objects things increase in amount as they are closer to the earth’s surface
1 pound. 2 pounds. 3 pounds. 4 pounds.
all of which all of them all that all what
A fixed star refers a star that is always stationary on the sky. Scientists can tell the motion of the earth from the motions of other five planets. Ancient people had scanty knowledge about the movement of the stars. All the stars on the sky can be seen all the year around.
move moveing to move be moved
reluctantly accidentally slowly carefully
until since after by the time
the same alike just as similar to
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