CREATE TABLE table_name_97 (longest_span_in_s_metre___feet__ VARCHAR, land VARCHAR, name VARCHAR)

How long is the UK's Ballochmyle Viaduct?
SELECT longest_span_in_s_metre___feet__ FROM table_name_97 WHERE land = "uk" AND name = "ballochmyle viaduct"
SELECT "longest_span_in_s_metre___feet__" FROM "table_name_97" WHERE "ballochmyle viaduct" = "name" AND "land" = "uk"