\((1)\)抛物线\(y^{2}=ax(a > 0)\)上的点\(P(\dfrac{3}{2},y_{0})\)到焦点\(F\)的距离为\(2\),则\(a=\)________.
\((2)\)已知递减等差数列\(\{a_{n}\}\)中,\(a_{3}=1\),\(a_{4}\)为\(a_{3}\),\(a_{4}+6\)等比中项,若\(S_{n}\)为数列\(\{a_{n}\}\)的前\(n\)项和,则\(S_{7}\)的值为________.
\((3)\)在四面体\(S-ABC\)中,\(AB⊥BC\),\(AB=BC=\sqrt{2}\),\(SA=SC=2\),二面角\(S-AC-B\)的余弦值是\(-\dfrac{\sqrt{3}}{3}\),则该四面体外接球的表面积是________.
\((4)\)设函数\(f(x)=\dfrac{{{x}^{2}}+1}{x}\),\(g(x)=\dfrac{x}{{{e}^{x}}}\),对任意\(x_{1}\),\(x_{2}∈(0,+∞)\),不等式\(\dfrac{g({{x}_{1}})}{k}\leqslant \dfrac{f({{x}_{2}})}{k+1}\)恒成立,则正数\(k\)的取值范围是________.