设int a=3;下列哪一个表达式的值等于0()。
A.a&&(a>0)
B.!a||a
C.a%=a
D.a>=a
参考答案:C
- Has your friend completed his design? - Not yet. He ________ on it last night.
A.worked
B.has worked
C.is working
D.was working
与茚三酮试剂能显色的是()
A.蛋白质
B.多糖
C.氨基酸
D.昆虫变态激素
E.甾醇