10.
\((1)\)若两圆\((x+1{)}^{2}+{y}^{2}=4 \)和\((x-a{)}^{2}+{y}^{2}=1 \)相交,则\(a\)的取值范围是________________.
\((2)\)已知函数\(f(x)=\begin{cases} & {{x}^{2}}+4x,x\geqslant 0 \\ & 4x-{{x}^{2}},x < 0 \\ \end{cases}\),若\(f(3-2a) < f(a)\),则实数\(a\)的取值范围是 ___.
\((3\)已知\(0 < k < 4 \),直线\({{l}_{1}}\):\(kx-2y-2k+8=0 \)和直线\({{l}_{2}} :2x+{{k}^{2}}y-4{{k}^{2}}-4=0\)与两坐标轴围成一个四边形,则使得这个四边形面积最小的\(k\)值为______.
\((4)\)已知\(A(0,2)\)是圆\(C\):\({x}^{2}+{y}^{2}=16 \)内的一点,\(D\)是圆上的动点,\(P\)是线段\(AD\)的中点,则点\(P\)的轨迹方程为____________________.