According to the table below, determine the type of variation between atmospheric pressure of a mountain and altitude.

x |
1 |
2 |
3 |
4 |
5 |
6 |
7 |

y |
120 |
60 |
40 |
30 |
24 |
20 |
17 |

a)What variation model does this table represent?

b)What is the model that relates y and x?

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