For each blank, choose the best answer fro

金属材料在生产、生活中有着广泛的应用。

(1)人类每年从自然界提取大量的金属，其中提取量最大的是铁。用赤铁矿(主要成分为Fe₂O₃)和一氧化碳炼铁的化学方程式为                                                   。

(2)北京奥运会用到多种材料。下列应用中使用金属材料的有                    (填序号)。

①使用金、银和铜等制作奖牌 ②使用纯羊毛和聚酯纤维制作“福娃”

③使用新型钢材建造“鸟巢” ④使用聚氟乙烯制造“水立方”外层膜

(3)金属矿物的储量有限，而且不能再生，所以保护金属资源尤为重要。保护金属资源的有效途径是                                                 (答出两条即可)。

一个200匝，面积0.2m²的均匀圆线圈，放在匀强磁场中，磁场方向与线圈垂直。若磁感应强度在0.05s内由0.1T增加到0.5T，则在此过程中，磁通量的变化率是=＿＿＿＿＿＿Wb/s，线圈中的感应电动势为E=＿＿＿＿＿＿V。

C is sometimes referred to as a ’high -level (66) language’. Some people think that’s an insult, but it’s actually a deliberate and significant aspect of the language. If you have (67) in assembly language, youll probably find C very natural and comfortable (although if you continue to focus too heavily on machine - level details, youll probably end up with unnecessarily non- portable programs). If you havent programmed in assembly language, you may be frustrated by C ’s lack of certain higher - level features. In either case, you should understand why C was de- signed this way: so that seemingly - simple constructions expressed in C would not expand to arbitrarily expensive ( in time or (68) ) machine language constructions when (69) . If you write a C program simply and succinctly, it is likely to result in a succinct, efficient machine language executable. If you find that the (70) resulting from a C program is not efficient, it’s probably because of something silly you did, not because of something the compiler did behind your back which you have no control over. In any case, there’s no point in complaining about C’s low - level flavor: C is what it is.

A. site B. place C. space D. dimension

关于精神疾病患者给家庭带来的负担，下列哪项是错误的：（）

A.精神病患者为家庭带来经济负担，对家庭成员的生活产生影响

B.精神病患者可对家庭成员造成人身伤害

C.家庭成员主观负担是指承受负担时的心理感受

D.精神病患者的所有家庭成员都承受同样的负担

E.不良社会功能也是构成家庭成员负担的原因之一

棉花的纤维的颜色棕色和白色是一对相对性状由一对等位基因（A，a）控制，棉酚含量含量的高低由另一对等位基因（B，b）控制，二对等位基因分别位于二对常染色体上且独立遗传。用纯合的棕色高酚品种和纯和的白色低酚品种杂交F₁全是棕色高酚，子一代自交产生F₂。

F₂中能够稳定遗传的占（）。