选词填空（每词只能用一次）。

cold, cool, warm, surprised, relaxed

1. She is ______ she can play the guitar well.

2. The boy in sun-glasses (太阳镜) looks ______ very much.

3. It‘s very ______ in spring.

4. It is ______, please wear your scarf.

5. The boys are really ______ in the park.

为了测定生铁中铁的质量分数，取生铁样品5.8g放入足量的硫酸溶液中，使之完全反应至无气泡产生（杂质不参加反应），所得氢气的质量为0.2g。请 计算该生铁样品中铁的质量分数（保留小数点后一位）。