题干
—Do you know that China is one of ________countries in the world? —Yes, I do. It's much ______than the US.
A：oldest; older
B：the oldest; older
C：the oldest; elder
D：the older; elder
答案(点此获取答案解析）
B
E(g)。当反应进行到4min时达到平衡，测得M的浓度为0．2 mol·L-1。下列说法正确的是
