The notes quote an accuracy value agreed with the UK CAA and taken from a pre-JAR textbook. Unfortunately the French didn't read the same textbook and their view of accuracy was based on a different system. Everything about the question except the accuracy ties in with the text, low altitude rad alts are FM, they (usually) operate between 0 and 2500ft, use continuous wave (CW) not pulsed signals and have an operating frequency range between 4200MHz and 4400MHz.

One can't complain about the French accuracy statement because it's actually more representative of a modern aircraft than the old CAA figures, even more representative figures would be +/- 1 ft in the first 1000ft.