. She is writing a letter to a friend of hers,     ___________     him to attend the meeting.

A．having invited

B．inviting

C．to invite

D．Invited

有三溶液：a.Ba(OH)₂，b.NaOH，c.NH₃·H₂O

（1）pH值相等时，三种溶液浓度由大到小的顺序为_________________

（2）物质的量浓度相等时，pH值由大到小的顺序为_________________

（3）pH=11时，各100mL与同浓度的HCl中和，消耗HCl体积由多到少的顺序为________________

（4）浓度相等时，各100mL与同浓度HCl中和，消耗HCl体积由多到少的顺序为_______________