10.
\((1)\)已知向量\( \overrightarrow{a}=(1,2) \),\( \overrightarrow{b}=(-2,1) \),则\( \overrightarrow{a} \)与\( \overrightarrow{b} \)的夹角为__________.
\((2)\)将一个正方形绕着它的一边所在的直线旋转一周,所得圆柱的体积为\(27πcm^{3}\),则该圆柱的侧面积为___________\(cm^{2}\).
\((3)\)表面积为\(24\)的正方体的顶点都在同一球面上,则该球的体积为
\((4)\)在正方体\(ABCD-{A}_{1}{B}_{1}{C}_{1}{D}_{1} \)中\((\)如图\()\),已知点\(P\)在直线\(BC_{1}\)上运动,则下列四个命题:
\(①d\)三棱锥\(A-{D}_{1}PC \)的体积不变;
\(②\)直线\(AP\)与平面\(ACD_{1}\)所成的角的大小不变;
\(③\)二面角\(P-A{D}_{1}-C \)的大小不变;
\(④M\)是平面\({A}_{1}{B}_{1}{C}_{1}{D}_{1} \)上到点\(D\)和\(C_{1}\)距离相等的点,则\(M\)点的轨迹是直线\(A_{1}D_{1}\)其中真命题的编号是__________\(.(\)写出所有真命题的编号\()\)