浓硫酸有许多重要的性质，在与含有水分的蔗糖作用过程中不能显示的性质是（   ）

欲配制100ml 1.0 mol/L  Na₂SO₄溶液，正确的方法是         （    ）
① 将14.2 g Na₂SO₄ 溶于100ml水中
② 将32.2g Na₂SO₄·10H₂O溶于少量水中，再用水稀释至100 ml
③ 将20 ml 5.0 mol/L Na₂SO₄溶液用水稀释至100 ml

阅读理解

A

While we are busy buying things for ourselves during festivals, we shouldn’t forget those members in our family, who love us without saying a word — our pets! This year, let’s make the festivals special for them by giving them some awesome gifts.    What else do pets love besides eating and playing? And when it comes to toys, we all know that pets are no different than kids, and every new toy would be welcomed with much excitement.

  Festivals give everybody a chance to dress up and look their best. Why should pets stay behind? Most pet stores have many choices(选择) when it comes to pet outfits(配备). From a cap to a T-shirt, if you want, you can get them in all types and sizes.

  Lastly, and most importantly, we all need love. So do our pets. Don’t ignore(忽视) them. Kiss them, love them, and play with them.

右图表示人类镰刀型细胞贫血症的病因，已知谷氨酸的密码子是GAA，由此分析正确的是   （ ）

某车间生产机器零件，如果每天比预定计划多做一件，8天所做零件的总数超过100件；如果每天比预定计划少做一件，那么8天可做零件的总数不到90件，则预定计划每天做多少件？（件数是正整数）