To make a base line mark to know where she started measuring the snails movement, at the end of the day she can measure from her first line to her last to see how far the snail went.
Hope this helped!
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Answer:
In animations, usually the sizes of the objects are does not appear to be right because they are made to show the basic features and what's generally happening in the above mentioned case. These inaccuracies are consciously made for the better understanding of the audience. So following are the inaccuracies,
B.The astronaut is too big compared to the moon.
D.The moon is too big compared to its orbit.
F.The moon is too big compared to earth.
