题干
We have sweaters ________ all colors ________ ￥50 each.
A：in, at
B：at, in
C：in, in
D：at, at
答案(点此获取答案解析）
A
We have sweaters ________ all colors ________ ￥50 each.
A：in, at
B：at, in
C：in, in
D：at, at
2B(g)+E(g)(正反应为吸热反应)达到平衡时，要使正反应速率降低，A的浓度增大，应采取的措施是