The calculated distance (air line) between Pervomaysk and Kryve Ozero is approximately 24 miles respectively 39 kilometers.
By car or train, the actual journey to Kryve Ozero is certainly longer, as only the direct route (as the crow flies) between Pervomaysk and Kryve Ozero has been calculated here.
Air line (approximately)
39 kilometers
21 nautical miles