A test of Radial Acceleration Relation for the {\it Giles et al Chandra}
  cluster sample
  We carry out a test of the radial acceleration relation (RAR) for a sample of
10 dynamically relaxed and cool-core galaxy clusters imaged by the Chandra
X-ray telescope, which was studied in Giles et al. For this sample, we observe
that the best-fit RAR shows a very tight residual scatter equal to 0.09 dex. We
obtain an acceleration scale of $1.59 \times 10^{-9} m/s^2$, which is about an
order of magnitude higher than that obtained for galaxies. Furthermore, the
best-fit RAR parameters differ from those estimated from some of the previously
analyzed cluster samples, which indicates that the acceleration scale found
from the RAR could be of an emergent nature, instead of a fundamental universal
scale.
