5.
I.在直角坐标版权法\(xOy\)中,直线\(l\)的参数方程为\(\begin{cases}x=3+ \dfrac{1}{2}t \\ y= \dfrac{ \sqrt{3}}{2}t\end{cases} \)\((t\)为参数\()\),以原点为极点,\(x\)轴的正半轴为极轴建立极坐标系,\(⊙C \)的极坐标方程为\(ρ=2 \sqrt{3}\sin θ \).
\((1)\)写出\(⊙C \)的直角坐标方程;
\((2)P\)为直线\(l\)上一动点,当\(P\)到圆心\(C\)的距离最小时,求点\(P\)的坐标.
\(II.\) 已知函数\(f\left(x\right)=\left|2x-a\right|+a \)
\((1)\)当\(a=2\)时,求不等式\(f\left(x\right)⩽6 \)的解集;
\((2)\)设函数\(g\left(x\right)=\left|2x-1\right| \),当\(x∈R \)时,\(f\left(x\right)+g\left(x\right)⩾3 \),求\(a\)的取值范围.