如图是某款电热水龙头的电路原理图,R1、R2为电热丝,通过旋转手柄可实现冷水、温水、热水档之间的切换,若R2=2R1,水龙头在温水档正常工作时电功率为2000W,则它在热水档正常工作时的功率为( )
A:1000W
B:2000W
C:3000W
D:4000W
友谊是一场精神的相遇,超越功利的友谊更长久。下列同学的说法与其一致的有( )
—How can we help the children in the mountain village?
—We can ____ leaflets to ask people to donate money.
如图,△OAB绕点O逆时针旋转80°到△OCD的位置,已知∠AOB=45°,则∠AOD等于( )