铁塔、桅杆的防雷引下线应采用不小于()的镀锌扁铁,并直接与()可靠连接。
参考答案:40×4mm;地网
During the month of October the Sun’s declination is().
A.north and increasing
B.north and decreasing
C.south and increasing
D.south and decreasing
研末服比煎汤效果好的中药是()
A.莱菔子
B.鸡内金
C.谷芽
D.山楂
E.麦芽