Which of the foliowing is a valid statement that declares variable kGravity as an unchangeable variable?

double kGravity$[9\mathrm{.}8]=$ readonly:

O const double kGravity:

canst double kGravity$[9\mathrm{.}8]$:

double $k$ Gravity $|9\mathrm{.}8|=$ const:

readonly doublekGravity $[9\mathrm{.}8\}$;