[googleapps domain="docs" dir="presentation/d/e/2PACX-1vQMDpkxp8-gWlKupVkUsHTOzoLqnSqkTO3Z-QaBQX81v71FPVVy8qQXEy1gYuvb3N3ro50F1AZmVM-i/embed" query="start=false&loop=false&delayms=3000" width="960" height="749" /]   https://youtu.be/_1eKL51oXZE   https://youtu.be/8VZHym6HqVU
[googleapps domain="docs" dir="presentation/d/e/2PACX-1vRo4GxMZISXazy5W64cO4FN2ZxvIybasp08hvwJ_KWldxEydueiRvRyBqwCIq2ia_Qm308PZ0Hs0mF7/embed" query="start=false&loop=false&delayms=3000" width="960" height="749" /]
[googleapps domain="docs" dir="presentation/d/e/2PACX-1vQS-VqOtnhYjHyyk_9wlu6nt4ns-9FM57NdC4BO_fXqUsWwjrR7gLvNmUcIMWLaLq_GOLZ3hHJp_1Al/embed" query="start=false&loop=false&delayms=3000" width="960" height="749" /]
[googleapps domain="docs" dir="presentation/d/e/2PACX-1vTFfYWtAu6EtRFtEhZ7vzdAK8z7vm5hswIScu5sK0JsoE6q9dSvRUohop9l38DXciEZc5krcJEgfi52/embed" query="start=false&loop=false&delayms=3000" width="960" height="749" /]
[googleapps domain="docs" dir="presentation/d/e/2PACX-1vTuDQzN-Id4qOXEvinM6v-l7D7QwF_qv50xImEerpceP9swf9x73byRSBnteINhfQ/embed" query="start=false&loop=false&delayms=3000" width="960" height="749" /]   동영상 내용 중 수정 사항 21" 태양의 나이: 50억 년 ⇒ 46억 년 26" 구성성분: 수소(92.1 %), 헬륨(7.8 %) ⇒ 수소(74.9 %), 헬륨(23.8 %)   https://youtu.be/ilKfYEhxBqs