三相负载接于三相供电线路上的原则是、若负载的额定电压等于电源线电压时，负载应作（）联结若负载的额定电压等于电源相电压时，负载应作Y联结。
参考答案：Δ
图中能正确表示北半球近地面风向与等压线关系的是
A、A
B、B
C、C
D、D
A 2-year certificate of deposit is purchased for k dollars. If the certificate earns interest at an annual rate of 6 percent compounded quarterly, which of the following represents the value, in dollars, of the certificate at the end of the 2 years ？（）
A．(1.06)2k
B．(1.06)8k
C．(1.015)2k
D．(1.015)8k
E．(1.03)4k
