Black Friday: lifetime access is on a special offer in the app, until November 30. Black Friday: special offer on lifetime access, until November 30. Download
이 연구에서는 접촉률을 높이는 방법을 조사했습니다.I yeongueseoneun jeopchokryureul nopineun bangbeobeul josahamnida.This study investigated ways to increase the contact rate.