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
비색계를 사용하여 물질의 색상을 측정합니다.bisaekgye-reul sayonghayeo muljil-ui saeksang-eul cheugjeonghamnida.We use a colorimeter to measure the color of the substance.