My friend Amy text messages to me on the mobile phone, but now she e-mails on QQ.
A:is used to send; used to send
B:used to send; is used to sending
C:used to send; used to send
D:is used to sending; used to send
如图所示是家庭电子式电能表的表盘,其示数是 ____ kW·h。表盘上标有“3200 imp/kW·h”,表示每消耗1kW·h的电能,指示灯闪烁3200次。若家庭电路中只有一台电热水器在工作,该电能表的指示灯在4 min内闪烁320次,则该热水器的实际功率是 ____ w。