已知一个角的补角等于这个角的余角的4倍,则这个角的度数是( )
A:30°
B:60°
C:90°
D:120°
在括号里填上“>”或“<”。
14-9____13-9 18-9____16-9
12-9____17-9 15-9____16-9
— _____ around the world is to learn about the world.
— Yes, it's a good way ____ the world.