【单选题】停电操作时,高压应先拉( ),后拉隔离开关。
【判断题】对于 的电力系统,当发生单相接地短路时,流过故障相的短路电流大小与三相短路相同,因此单相短路对电力系统并列运行暂态稳定性的影响也与三相短路相同。
【简答题】(1) 已知直线 y = mx - 2 m + 2( m ≠ 0) .求证:无论 m 为何值,直线必经过一定点,并求出此定点坐标; (2) 求直线 y = ( m + 2) x + m 所经过的定点坐标.
【单选题】由一组样本数据(x 1 ,y 1 ),(x 2 ,y 2 ),…(x n ,y n )得到的回归直线 ,那么下面说法不正确的是( )
B.
直线 至少经过点(x 1 ,y 1 ),(x 2 ,y 2 ), …(x n ,y n )中的一个点
D.
直线 和各点(x 1 ,y 1 ),( ), …(x n ,y n )的偏差和 是该坐标平面上所有直线与这些点的偏差和中最小的直线
【简答题】A.false B.stupid C.true D.faithful
【简答题】A.false B.stupid C.true D.faithful
【简答题】A.accurate B.true C.certain D.faithful
【简答题】(1) 已知直线 y = mx - 2 m + 2( m ≠ 0) .求证:无论 m 为何值,直线必经过一定点,并求出此定点坐标; (2) 求直线 y = ( m + 2) x + m 所经过的定点坐标.
【单选题】Which ONE of the following statements describes faithful representation, a qualitative characteristic of faithful representation?
A.
Revenue earned must be matched against the expenditure incurred in earning it.
B.
Having information available to decision-makers in time to be capable of influencing their decisions.
C.
The presentation and classification of items in the financial statements should stay the same from one period to the next.
D.
Financial information should be complete, neutral and free from error.
【单选题】停电操作时,高压应先拉( ),后拉隔离开关