2025年5月国际A卷 · 第 11 题

The function \( f(x)=\frac{1}{7}(x−6)^{2}+4 \)  gives a toy car's height above the ground \( f(x) \) , in inches, x seconds after it started moving on an elevated track, where \( 0\le x\le10 \). Which of the following is the best interpretation of the vertex of the graph of \( y=f(x) \)  in the xy-plane?