6.
如图所示,正方体 \(ABCD\)\(\) \(A\)\({\,\!}_{1}\) \(B\)\({\,\!}_{1}\) \(C\)\({\,\!}_{1}\) \(D\)\({\,\!}_{1}\)中, \(M\), \(N\)分别是 \(A\)\({\,\!}_{1}\) \(B\)\({\,\!}_{1}\), \(B\)\({\,\!}_{1}\) \(C\)\({\,\!}_{1}\)的中点\(.\)问:
\((1)\)\(AM\)和\(CN\)是否是异面直线?说明理由;
\((2)\)\(D\)\({\,\!}_{1}\)\(B\)和\(CC\)\({\,\!}_{1}\)是否是异面直线?说明理由.