3.
如图,已知正方体\(ABCD-{A}_{1}{B}_{1}{C}_{1}{D}_{1} \)中,\(F\)为线段\(B{C}_{1} \)的中点,\(E\)为线段\({A}_{1}{C}_{1} \)上的动点,则下列四个结论:
\((1)\)存在点\(E\),使\(EF/\!/BD \);
\((2)\)存在点\(E\),使\(EF⊥ \)平面\(A{B}_{1}{C}_{1}D \);
\((3)EF\)与\(A{D}_{1} \)所成的角不可能等于\(60^{\circ}\);
\((4)\)三棱锥\({B}_{1}-ACE \)的体积随动点\(E\)而变化.
其中正确的是______ .