阅读理解
Danny: Good morning, Jenny.
Jenny: Good morning, Danny.
Danny: Oh, Jenny , this is my sister Kate. She is a teacher.
Kate: Nice to meet you ,Jenny.
Jenny: Nice to meet you , too, Are those your students?
Kate: Yes , they are.
Jenny: And , Who is he?
Danny: He's my brother, Jack.
Jenny: Oh, I see. Well, have a good day!
Jenny\Kate: Thanks! You , too . Bye!
3C(g)+D(g),当加入4 mol A和2 molB达化学平衡时,C的物质的量浓度为m mol·L-1,若维持温度不变, 按下列四种配比为起始物质, 达到化学平衡后,C仍为m mol·L-1的是
