阅读图文材料，完成下列要求。

材料一：橙，是一种柑果，喜温，不耐寒，生长土壤pH值在5.5~7.0之间为好。

材料二：新平县嘎洒镇位于元江上游嘎洒江沿岸，主要以河谷与山地为主，青山绿水。近年来，在当地政府鼓励下，将荒地承包出支，种植褚橙，逐渐发展成为我国冰糖橙生产基地之一；褚橙主要种植在河谷地势较高的滩地上，收获后一部分直接销往市场，其余搬运到山腰存放。图5是云南省新平县等高线地形图。

根据短文内容, 选择正确答案。

There are many holidays and festivals. Dads have Father's Day. Children have Children's Day. Is there a special day for old people?

Double Ninth Festival is a special day for old people in China. It started long ago. The festival is on lunar September 9th. This year it is on October 13th. On this day, people show love for their grandparents.

People do many different kinds of things on this day. They enjoy flowers, eat special cakes and drink wine(酒).

      It's very interesting. The best way to celebrate it is climbing hills or mountains. People think climbing will bring them good luck and help old people live long lives. Double Ninth Festival is also a good time for a family get-together. And young people give their presents and best wishes to the old.

①它通常在白天爬升至平流层20千米至30千米的高度，将太阳能最大限度地转存到储能电池中，夜晚则逐渐降至15千米至18千米的高度，低速、半滑翔飞行。

②太阳能飞机是以太阳辐射的光能为动力的飞机。

③同时，由于太阳能飞机以太阳能为动力，故其燃油、维护和维修费用基本为零。

④太阳能飞机源源不断的动力，使它一次飞行可长达数月乃至数年。

⑤与常规飞行器相比，太阳能飞机由于不需要传统的化石燃料，因此具有自己独特的优势。