1. If the bond axis is z-axis, which of the following atomic orbitals cannot form σ bond A: s-s B: s-pz C: px-px D: pz-pz

_______ indicates that the zero,Y,Z return is over for the respective axis X.

For a hydrogen atom in the 6f state, the minimum angle between the orbital angular momentum vector and the z axis is (  )

下列程序运行后，看到的图形是（）。[x,y,z]=cylinder(10,40);surf(x,y,z)view(90,0);axis square

纵、横坐标轴采用等长刻度的命令是 A: axis square B: axis auto C: axis equal D: axis off

以下属于坐标轴控制的命令的是？ A: axis auto B: axis tight C: axis fill D: axis ij

下列程序运行后，看到的图形（ ?????）。 ?????t=0:pi/6:2*pi;[x,y,z]=cylinder(t, 6);surf(x,y,z)view(0,90);axis equal

If you want to get the axis like following figure, how to set the axis?[img=570x508]17de94b382954af.png[/img] A: axis( [ 0 10 15 -10 ] ); B: axis( [ -10 15 0 10 ] ); C: axis( [ 0 10 -10 15 ] ); D: axis( [ 0 -10 10 15 ] );

下列程序运行后，看到的图形（）。t=0:pi/6:2*pi;[x,y,z]=...ew(0,90);axis equal

将df的行索引降序+列索引升序排序，正确的方法是（ ）。 A: 先df.sort_index(axis = 0,ascending = False)，然后df.sort_index(axis = 0,ascending = True) 。 B: df.sort_index(axis = 0,ascending = True).sort_index(axis = 1,ascending = False)。 C: df.sort_index(axis = 0,ascending = False).sort_index(axis = 1)。 D: 先df.sort_index(axis = 0,ascending = False)，然后df.sort_index(axis = 0) 。