【单选题】给出下列说法: 两条直线被第三条直线所截,同位角相等; 平面内的一条直线和两条平行线中的一条相交,则它与另一条也相交; 相等的两个角是对顶角; 从直线外一点到这条直线的垂线段,叫做这点到直线的距离; 其中正确的有( )
【单选题】给出下列四个命题: (1)平面内的一条直线与平面外的一条直线是异面直线; (2)若三个平面两两相交,则这三个平面把空间分成7部分; (3)用一个面去截棱锥,底面与截面之间的部分叫棱台; (4)一条直线与两条异面直线中的一条直线相交,那么它和另一条直线可能相交、平行或异面. 其中真命题的个数是( )
【单选题】A trial balance prepared before any adjustments have been recorded is:
A.
An adjusted trial balance.
B.
Used to prepare financial statements.
C.
An unadjusted trial balance.
D.
Correct with respect to proper balance sheet and income statement amounts.
E.
Only prepared once a year.
【单选题】In Trial 5, is it likely that bubbles were present in large numbers immediately before the can was shaken?
A.
Yes; based on the results of Experiment 1, the bubbles produced in Trial 4 probably lasted for less than 15 min.
B.
Yes; based on the results of Experiment 1, the bubbles produced in Trial 4 probably lasted for more than 2 hr.
C.
No; based on the results of Experiment 3, the bubbles produced in Trial 4 probably lasted for less than 2 hr.
D.
No; based on the results of Experiment 3, the bubbles produced in Trial 4 probably lasted for more than 3 hr.
【多选题】延缓果实后熟进程的主要相关基因有:A: PG基因B:ACC合成酶基因(ACS)C:ACC氧化酶基因(ACO)D:ACC脱氨酶基因
【单选题】.下列四个命题 ① 分别和两条异面直线均相交的两条直线一定是异面直线. ② 一个平面内任意一点到另一个平面之距离均相等,那么这两个平面平行. ③ 一个二面角的两个半平面分别垂直于另一个二面角的两个半平面,则这两个二面角的平 面角相等或互补. ④ 过两异面直线外一点能作且只能作出一条直线和这两条异面直线同时相交.其中正确命 题的个数是
【简答题】已知形体的两个视图,选择正确的第三视图。
【单选题】巡航系统、前照灯智能控制系统、自适应巡航系统的建成分别是。( )