—I know you ______ to China many years ago. And how long have you ______ in China ?—I don't remember

题干

—I know you ______ to China many years ago. And how long have you ______ in China ?

—I don't remember it exactly.

A：come, live

B：came; come

C：come; come

D：came; lived

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广告费用x（万元）	2	3	4	5	6
销售轿车y（台数）	3	4	6	10	12

根据数据表可得回归直线方程 $\hat{y}$ = $\hat{b}$ x+ $\hat{a}$ ，其中 $\hat{b}$ =2.4， $\hat{a}$ = $\bar{y}$ ﹣ $\hat{b}$ $\bar{x}$ ，据此模型预测广告费用为9万元时，销售轿车台数为（）