判断题 全波整流时负载上的平均电压是半波整流情况下的2倍。

单项选择题 Brain Co is considering launching a new product. Expected sales volumes (at a selling price of $5 per unit) and expected unit variable costs are as follows. Sales Variable costs per unit Units Probability $ Probability 1,000 0.9 1.30 0.60 2,000 0.1 1.50 0.40 Fixed costs are expected to be $2,000. The company produces to order. What is the expected profit? A、$2,400B、$30C、$1,982D、$971

单项选择题 在运动会上，你追我赶，同学们一同体验成功的兴奋；在诗歌欣赏会上，同学们得到了心灵的净化；在劳动时，同学们共享收获的喜悦；看到中国女排重夺奥运会冠军，同学们心中充满自豪和骄傲。这说明（）①我们通过情感体验生命、体验生活②情感让我们的内心世界更加丰富③情感与情绪关系不大④情绪是稳定的，情感是不稳定的