It would be a combination of translation symmetry (which is present in all patterns), followed by a reflection about a vertical line (hence the m), followed by the 180° rotation about a point on the midline (hence the 2).
The symmetry described is equivalent to pattern #7, so it can also be described as having translation symmetry, glide reflection, and reflection over a vertical line. So it could also be classified as mg.
If you consider symmetry in the basic design element part of the symmetry of the frieze pattern, you may have slightly different answers than the ones here. In the order in which the designs are given, the classifications are as follows:
12, 11 (or possibly m1), m1, 11 (or possibly 1m), 11, 11 (or possibly m1), 11 (or possibly 1m), 11 (or possibly mm), 12, m1 (or possibly mm), m1 (or possibly mm), and 11 (or possibly 1m).