把a g铁铝合金粉末溶于足量盐酸中，加入过量NaOH 溶液．过滤出沉淀，经洗涤、干燥、灼烧，得到红棕色粉末的质量仍为a g，则原合金中铁的质量分数为（ ）
种豆得豆种瓜得瓜是因为亲代把（ ）传给了子代．
-- Anna, could you lend me this book, please?
-- I'm sorry. I it for only two days, and I haven't finished it yet.
