—________
A:I'm sorry to hear that
B:I'm disappointed
C:Good luck
Spring comes. good season it is!Let's take a walk.
①写作业 ②睡觉
样品 →①加水 溶液 →②试剂A 浊液 →③K2CO3 滤液 →④盐酸 溶液
回答下列问题: