请结合图1回答问题：

某化学研究性学习小组拟对一种焰火原料（由两种短周期的常见金属单质Li，Na，Mg，Al组成的合金粉末）进行探究．请完成下列探究报告．

【探究目的】探究该焰火原料的组成

【资料检索】①Mg²⁺检验方法：取2滴待检液，加入2滴2mol•L^﹣1NaOH溶液，再加入1滴镁试剂（Ⅰ）染料（对硝基苯偶氮苯二酚）．若出现沉淀并吸附镁试剂（Ⅰ）染料呈天蓝色，表示待检液中含有Mg²⁺．但Ag⁺、Cu²⁺、Fe³⁺、NH₄⁺会妨碍Mg²⁺检出

②Mg（OH）₂可溶于浓的氯化铵溶液，其他的常见不溶碱难溶于氯化铵

③很多合金是金属互化物，有确定的化学组成

【探究思路】①确定焰火原料所含金属种类；②测定焰火原料的化学式

【实验探究】

对植物细胞起支持和保护作用的结构是

    I have eight teachers now and I love them. My favorite teacher is my English teacher, Sophia.

    Sophia is an English woman. She loves Chongqing. She thinks Chongqing is great. She loves Chongqing food.她早餐吃什么？Bread and milk? No. She only has noodles (面条)。 Hot pot(火锅)is her favorite . She always eats it in the evening on Friday .Sophia has a daughter and a son. They are eight.他们去相同的学校。 They like hot pot, too. They are in Chongqing,too.

    My classmates like to play English games with Sophia. When we have questions, we like to ask her for help.

This black bag is very nice, but it"s very____（重的）.