第1题: [单项选择]Green plants combine __________ with water and carbon dioxide to make food. A. ( energy derived from light B. ( energy, derived it from light C. ( energy is derived from light D. ( from light, and energy derived 参考答案:A
第27题: [单项选择]某风电场升压站的110kV主接线采用变压器线路组接线,一台变压器容量为100MVA,主变压器短路阻抗为10.5%,110kV配电装置采用屋外敞开式,升压变压器地处海拔1000m以下,站区属多雷区。若进行该风电场升压站110kV母线侧单相短路电流计算,取S=100MVA,经过计算网络的化简,各序计算总阻抗如下:请按照《电力工程电气设计手册电气一次部分》,计算单相短路电流的周期分量起始有效值最接近下列哪项数值()? A. 3.387kA B. 1.129kA C. 1.956kA D. 1.694kA 参考答案:A