简述黄铁矿化学组成。
参考答案:
Fe46.55%、S53.45%。常有Co和Ni的类质同像。黄铁矿是制备硫酸的重要原料,也是目前撮取钴的主要矿物。
How does Fred spend one week?
小题1:Where does Fred meet Ann?
A.At Brown’s house
B.In the hospital
C.At the station
D.At Kay’s house小题2:For how many hours a week does Fred do his part—time job?
A.Five hours
B.Six hours.
C.Ten hours
D.Eleven hours小题3: is ill in hospital.
A.Brown
B.Joy
C.Tom
D.Kay小题4:Kay’s birthday is on .
A.Tuesday
B.Friday
C.Sunday
D.Thursday小题5:What does Fred do on Saturday afternoon?
A.Play football
B.Study with Tom
C.Have a dancing class
D.Do part—time job
有报纸载文感叹:“我数千年历史之蚕桑事,不沦亡于敌伪铁蹄之下,而消灭于……官僚资本之压迫榨取也!吾民何辜,惟此浩劫!”此种状况出现于 [ ]
A. 1927年南京国民政府的成立
B.国民政府的前十年(1927-1936年)
C.抗日战争时期
D.抗日战争胜利以后