Self-study
The largest volcano on Mars rises 27 kilometers above the surrounding plain and covers an area roughly the size of Romania. ████ ██ ███ ███████ ███████ ████ ██ ███ ██ ███ ███████ ██ ████ ███ ██ ███████ ██ ████ ████ █████ █████ ██ ██████ ███ ███ ███████ ██████ ████████ ██ ███████████ ███ ████ ███████████ ██ ████ ██ █████ ██ ███ ████ ██ ███████ ████ █ █████ ████████ ██ ████ ████ ███ █████ ██████ █████ ███ ███████ ███ ████████ ██ █████
Summary
The Earth’s crust is too thin to support a volcano as big as the largest one on Mars.
Notable Valid Inferences
The Earth’s crust is generally thinner than Mars’s crust. The thickness of Mars’s crust enables large volcanoes to form on it.
6.
If the statements above are █████ █████ ███ ██ ███ █████████ ████ ████ ██ ████ ██ ███ █████ ██ █████
a
The surface of ████ ██ ████ ███████ ██ ██████ ██ ███████ ████ ██ ███ ███████ ██ ███ ██████
This could be false. We don’t know which planet is subject to less erosion than the other, and we have no information to suggest whether this is true or false.
b
The highest volcanoes ██ ████ █████ █████ ███ █████ ██ █████████
This could be false. It could be that Mars’s thick crust is necessary for large volcanoes to form, but other factors determine how large they can get. In other words, a thick crust could be necessary, but not sufficient, for large volcanoes.
c
On average, volcanoes ██ ████ ███ ██████ ████ █████ ██ ██████
This could be false. We only know about one very large volcano on Mars. For all we know, all the other volcanoes could be very small and Earth’s are, on average, higher.
d
The crust of █████ ██ █████ ██ ███████ ██████ ██ ███ ███████ ██ ███████ ████ ███ █████ ██ ███ ██████
This must be true. The stimulus tells us that Earth cannot support such large volcanoes because its crust is too thin. This implies that Mars’s crust is not too thin (i.e., it is thicker), which enables it to support such a large volcano.
e
At least some ██ ███ ███████ █████████ █████ ██ ██████ ████ ████ ████████ ███ ██ ███ ███████ █████ ████ ███████ ████ ██ ███
This could be false. It could be that crust thickness determines whether large mountains can form, but other factors determine whether they end up forming and how big they get. It could be that a thick crust is necessary, but not sufficient, for large volcanoes.