PowerPoint
2019
1

6
7

8









30%
40%
20% 20% 20% 20% 20%
25% 25% 25% 25%



13



( )








20%
20%
20%
30%






(1 2 3 )30%
, 40%




1



17



1 2 3 30%
40%
30%
30%








71+ 31(



10%
15%
30%
50%
20%
20%
20%
30%
30%
40%
30%
30%
40%
30%


10%
15%
8


9
2~





26
108






1
2





100
mp3mp4 5MB
mp3mp4 5MB