The Shenzhou IX spacecraft returned to the earth safely _______ June 29th, 2012.
A:at
B:in
C:on
D:from
52-7=____8+32=____28+10=____30-7=____74+26=____
18+3=____100-92=____64-9=____40+10=____ 75-5=____
《清明上河图》描绘了北宋都城的繁荣景象,其作者是 ( )