皮皮学，免费搜题
登录
搜题
【单选题】
____ we are doing has never been done before.A.
What
B.
Which
C.
That
D.
Whether
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【单选题】The currencies generally referred to as "reserve currencies" are the:
A.
Japanese yen and U.S. dollar
B.
Swiss franc and Japanese yen
C.
British pound and U.S. dollar
D.
Swiss franc and British pound
【简答题】The currencies of the countries of the Euroland were phasing out in 200