每年的6月5日的“世界环境日”都有一个主题，今年的主题是：（）。
参考答案：让地球充满生机
—Why can't you and Bill go to the movies tonight?
—We are _____ a history test tomorrow.[ ]
A. supposed to having
B. supposedly to have
C. supposed to have
D. supposedly to having
A．电流表的示数为3/11 A
B．通过灯泡的电流的频率为50Hz
C．电流表的示数为3/22 A
D．理想变压器原、副线圈匝数之比为2:1
sin100πt （V）的 正弦交流电源，图中电流表内阻不计．副线圈接入“110V，60W”灯泡一只，且灯光正常发光．下列说法正确的是（ ）
/22 A