The answer is:
1- A line of symmetry will connect a vertex and a midpoint of an opposite side.
2- It has -fold symmetry.
The explanation for this answer is shown below:
1- By definition, a line of symmetry is an imaginary line that divides a figure into two equal images or equal halves. If you connect a vertex and a midpoint of an opposite side of an heptagon by drawing a line, you will obtain two equal halves.
2- An heptagon has seven vertices, therefore, based on the information mentioned above, it has -fold symmetry.