Question: What is the c (nf/km) when the r (ω/km) is 463.59?
Schema: create table table_261642_3 (c__nf_km_ varchar, r__ω_km_ varchar, PRIMARY KEY (c__nf_km_))
SQL: select c__nf_km_ from table_261642_3 where r__ω_km_ = "463.59"