人力安装预制构件执行什么定额？
参考答案：
使用机械、人力安装预制构件，均执行构件安装相应定额。
函数f（x）=2sinxcosx的最小正周期是______．
The expression FIRST MAGNITUDE is usually used to refer only to bodies of magnitude（）.
A.1.5 and greater
B.1.25 and greater
C.1.0 and greater
D.0.5 and greater
