在一定温度下,下列物质以溶解度的大小顺序排列正确的是()。
A、烧碱>石膏>硫酸钡
B、硫酸钡>烧碱>石膏
C、石膏>烧碱>硫酸钡
D、烧碱>硫酸钡>石膏
参考答案:A
如果x、y的值满足3x-y-7=0,2x+3y=1,y=kx+9,则k的值应等于( )。
The new bridge _____ by the famous architect is _____ now. [ ]
A. designing, under construction
B. designed, under construction
C. being designed, under construction
D. has been designed, under the construction