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
물체의 작용력은 그 물체의 운동에 영향을 미친다.Mulche-ui jak-yongnyeok-eun geu mulche-ui undong-e yeonghyang-eul michinda.The action force of an object affects the motion of that object.