A:40°
B:50°
C:90°
D:130°
已知 a+2 +|b+1|=0,那么(a+b)2007的值为( )
下列有关神经调节和体液调节的说法正确的是( )
Look at the lovely dog. Guess _______ at birth. I think he might be 100 grams.