合上所有空气开关、隔离开关，将功能选择开向“自动”，各本地柜的开关选择“自动”方可组合启动。
参考答案：对
When smaller amounts of additional labor are supplied in response to increases in the wages offered, this is known as the:（）
A. substitution effect.
B. income effect.
C. marginal rate of substitution.
