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Math·Problem-Solving and Data Analysis·Two-variable data: Models and scatterplots

hard

The scatterplot shows the relationship between $x$ and $y$ for the 9 data points in data set A.

A quadratic model for the data in data set A can be written as $y=0.07x^2-0.06x+6.32$. The graph of this model is shown in the xy-plane. The data point at $x=0$ was found to be the result of a recording error and was removed from data set A to create data set B, consisting of the remaining 8 data points. A quadratic model for the data in data set B can be written as $y=a{x}^2+bx+c$, where $a$, $b$, and $c$ are constants. If the quadratic models for data sets A and B are calculated in the same way, which of the following statements must be true?

I. $a>0.07$
II. $c<6.32$

A

I only

B

II only

C

I and II

D

Neither I nor II