I would say it is plural.
Since the number behind it is a zero the number would stay the same
<span>Felicity can mean happiness; but in the case of the
passage in “The Count of Monte Cristo” where the man bowed in prayer then
became transformed from “convulsive(ly)” to becoming “calmer and more happy,”
the more appropriate meaning would be pleasure and luck or blessedness. It came
as some kind of a realization that he has been fortunate after all.</span>
