8.
\((1)\)向量\( \overrightarrow{a}=\left(1,2,-2\right), \overrightarrow{b}=\left(-2,x,y\right), \)且\( \overrightarrow{a}/\!/ \overrightarrow{b} \)则\(x-y=\)________
\((2)\)下方茎叶图记录了甲、乙两组各\(5\)名学生在一次英语听力测试中的成绩\((\)单位:分\().\)已知甲组数据的中位数为\({14}\),乙组数据的平均数为\({16}\),则\(x+y\)的值为__________.
\((3)\)已知直线\( \sqrt{3}x-y+2=0\)及直线\( \sqrt{3}x-y-10=0\)截圆\(C\)所得的弦长均为\(8\),则圆\(C\)的面积是________.
\((4)\)已知\({F}\)是双曲线\(C:{{x}^{2}}-\dfrac{{{y}^{2}}}{8}=1\)的右焦点,\(P\)是\(C\)左支上一点,\(A\left( 0,6\sqrt{6} \right)\) ,当\(\Delta APF\)周长最小时,该三角形的面积为________.