忽如一夜春风来，万辆单车遍地开，合肥投入大量共享单车，从环保角度，共享单车的使用（    ）

①给人民生活带来便捷

②主要为了解决交通压力

③有利于人与自然的和谐共处

④符合可持续发展的要求

右图是某种植物正常的体细胞（示细胞中所有的染色体）。试判断该植物可能的基因型及细胞中所含的染色体组数是（ 　 ）

目前西部地区因生态环境破坏所造成的直接经济损失达1 500亿元。回答以下小题.

课文填空

    The skin is ____ essential part of your body and its ____ organ. You have three ____ of skin which act as a barrier ____ disease, poisons and the sun's harmful rays. The ____ of your skin are also very ____: it keeps you warm or cool; it prevents your body from ____ too much water; it is where you feel cold, heat or pain it gives you your sense of ____. So you can imagine, if your skin gets ____ it can be very serious. First aid is a very important first step in the ____ of burns.