--- We really enjoyed ourselves at the party. Thanks again, Mr and Mrs Johnson.

---____. Just drop in whenever you feel like it.

A．With pleasure

B．Our great honor

C．Nice to meet you here

D．Nice having met you here

请使用卡西欧FX-3950P计算器编程计算表4-2竖直角观测的指标差及竖直角。