A:③④
B:②③
C:①④
D:②④
已知一次函数y=kx+b的图象如图,则k、b的符号是( )
地球的平均半径是( )
- Is Jack in the next room?
- Well, it's hard to say. But I heard him ________ loudly when I passed by just now.
-- Could you show me the method of cooking the tasty cookies?
-- Please follow the ______ on the cookbook.