Answer:
Knowing that a simile is a comparison between two things/ideas using the words "like" or "as"--->
A roller coaster can feel like flying because similar to how you would imagine flying to feel like (almost free-falling, liberated, vulnerable, yet invigorating, etc.), a roller coaster enables you to feel the same way, you are high up in the air racing at fast speeds and looping in some way that somehow defies the laws of physics ✨ yes fun stuff
Essentially, roller coasters can feel like flying because flying and roller coasters give the same feelings of excitement and also being high up in the air, since being on the ground won't take ya anywhere.
1) x=9, because we can use the Pythagorean theorem, x^2 + 144 = 225, x^2 = 81
2) 
, because 6^2 +6^2 = 72, 
3) 
, because 
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