How to split and join video using FFMPEG?

Question

Video processing

A question. There is a video of 10 minutes + there is a video of 5 seconds.
What you need:
1) divide a 10-minute video into 55-second segments (the latter will obviously turn out a little less).
2) attach a 5-second video in each segment (that is, glue)
3) as a result, you get 10 = 1 minute video + 1 a little less than a minute.
FFMPEG program, the format of all MP4 videos.