— Did you enjoy yourself at the dinner party?
— Yes, I’ve never been to________one before.

下列各选项所述的两个量 , 前者一定大于后者的是: ① F₂和Br₂的沸点 ②纯水在 25 ℃和 80 ℃时的 pH 值 ③同温下分别在1OOg水中最多能溶解的无水 CuSO₅和 CuSO₅· 5H₂O的质量 ④ 25 ℃时 ,等体积的 pH 值都等于3的盐酸和AlCl₃溶液中 ,已电离的水分子数 ⑤在NH₃＋NO→ N₂十H₂0 反应中 , 被氧化和被还原的N 原子数 ⑥耐火材料 MgO 和 CaO 的熔点 ⑦ H^-和H⁺离子半径 ⑧金刚石晶体和石墨晶体中 , 每个最小碳环里所含的实际碳原子数

根据短文理解，选择正确答案。

    The size and shape of your ears show your character more than any other part of the face. Other parts of the face change shapes as we get older, but ears do not change their shape. They only change in size.

    Reading people's character from their ears is a very old science. In the past people thought that a person's ears with colour was dangerous. They also thought that the shape of the ears showed if a person was musical or not. Today, too many people believe that the size and shape of the ears help you know if a person is musical.

    Ears are all different, and each different thing has a meaning. Next time you look at a person, see if his or her ears are large, medium-size, or small. Look at the lobes（耳垂）. Do they stick to the face? Ears that are always red mean that a person may get angry easily. Ears that are always cold and nearly white colour mean that a person has a nervous(紧张的) character.

一个体积为的正三棱柱的三视图如图所示，则这个
三棱柱的左视图的面积为                （   ）

鲁班是我国一位伟大的发明家，他发明了锯。（   ）