Explanation for Question 24 From the Reading Section on the 2017 April Sat
Okay. According to the passage, the nice model is based on the idea that 2 what, so we're referring to this particular model and we want to know what 3 is it particularly based on. Um, 4 so remember this model is being discussed here. 5 Um, according to this idea, 6 um, the two planets went rampaging through the solar system around 3.9 billion 7 years ago. It says that many of the icy objects that formed 8 in the outer solar system were pulled inward by the gravity of the two 9 planets. So their gravity was kind of impactful in this trend. 10 Um, and some ended up joining the Rocky asteroids that were born in the 11 asteroid belt. So this is talking about, 12 um, how orbits of the planets used to be unstable and how this 13 caused, um, these two planets to go rampaging around the outer solar system and 14 kind of affecting the dispersion of all of these different icy objects in the 15 outer solar system, because they were pulling it, 16 um, that those objects inward by their gravity. 17 Um, so looking at the answer choices to this question, 18 um, answer choice, I says Uranus and Neptune were not always locked into their 19 current orbital paths. Um, 20 when they say not always locked into their current orbital paths, 21 um, that matches up pretty well with this idea of them being, 22 having unstable orbits that's described here. 23 And this is kind of presented as the basis of the nice model. 24 So answer choice a is going to be our correct answer, 25 um, both because of how...