99色精品-9色在线-99色在线-99色视频 国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

單項(xiàng)選擇題

If two AC generators are operated in parallel, the load is distributed evenly by()

A.a rheostat
B.a balancing coil
C.changing field excitation
D.adjusting the governor settings

微信掃碼免費(fèi)搜題