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
원자로의 제어봉은 핵 반응을 조절하는 데 사용됩니다.wonjaroui je-eobongeun haek ban-eungeul jojeolhaneun de sayongdoemnida.The control rods of the reactor are used to regulate the nuclear reaction.