Lily wants to track her store’s progress as time goes on. She makes a table of values with one variable being time in weeks and the other variable being the amount of money the store makes in thousands of dollars. Find a polynomial function that models Lily’s sales.

Time (x) |
1 |
2 |
3 |
4 |
5 |
6 |
7 |

Revenue (y) |
0.5 |
3 |
9.5 |
23 |
46.5 |
83 |
135.5 |

^{3}-2n^{2}+2n-1

^{3}-n^{2}-1

^{3}-n^{2}+2n-1

^{3}-n^{2}+1/3
n-1