A:90°
B:60°
C:30°
D:15°
I ______ have worried before I came to the new school, for my classmates here are very friendly to me.
“春节”“中秋节”都是中国传统节日,但现在有许多西方节日传入我国。如“圣诞节”、“复活节”、“感恩节”。你知道这些节日与哪一宗教有关吗( )
具有下列染色体数一般不可能是体细胞的是( )