RONV $($a$)$ Var. $($c$)$ Var. $($c$)$ Var. $($d$)$ Var. $41..?($a$)($c$)($d$)()42.-($a$)600-700($b$)400-500($c$)350-400($d$)200-250809380-70250\text{'}\text{'}?($a$)($b$)($c$)($d$)\text{'}\text{'}?($a$)($b$)($c$)($d$)$