有些类型的文件因为它们本身就是以压缩格式存储的，因而很难进行压缩，例如（）。 A.W

下列命题为真命题的是（　　）

A．90°的圆周角所对的弦是圆的直径

B．三点确定一个圆

C．平分弦的直径必垂直于弦

D．相等的圆心角所对的弦相等

如图所示，甲、乙、丙为对胚芽鞘不同处理的实验，丁为一植株被纸盒罩住，纸盒的一侧开口，有单侧光照。下列对实验结果的描述，正确的是

A．甲、乙向光弯曲生长，丙背光弯曲生长

B．甲直立生长，乙、丙向光弯曲生长

C．丁图中如果固定植株，旋转纸盒，一段时间后，植株向左弯曲生长

D．丁图中如果将纸盒和植株一起旋转，则植株弯向纸盒开口方向生长

中国进出口银行出口信贷优惠利率，主要用于支持（）境外投资重点项目。

A.大型国有企业的

B.能带动国内技术、产品、设备等出口的

C.能弥补国内资源相对不足的

D.有能力按时还本付息的

E.加快开拓国际市场的

女，34岁，素食者，面色苍白，倦怠无力，头晕，耳鸣。查体：血压110／70mmHg，心率103次／分。检验：红细胞2．6×10¹²／L，血红蛋白94g／L。

该患者出现上述症状最可能的原因为（）

A.钙摄入不足

B.钙摄入过多

C.铁摄入不足

D.铁摄入过多

E.钠摄入不足

B Egyptian Villages 埃及村落

Most of the inhabitants live in mud-brick homes, their (1)  walls insulating against the afternoon heat. Flat roofs, exposed (2)  the northern evening breezes, serve as cool sleeping (3)  as well as storage areas. Villagers plaster the outer walls (4)  often trim them in blue, a color they believe (5)  off the evil eye. As a man becomes richer, (6)  can add a second story to his house perhaps (7)  his married son. Those villagers who have made the (8)  to Mecca paint the legend of their trip on (9)  outer walls of their homes. Such hajj houses, along (10)  the mosques, are the most distinguished buildings in a (11)

Some villagers build ornate pigeon coops close to their (12) , using the birds as food and their droppings to (13)  crops. Many houses still have dirt floors and lack (14)  or running water; women with jars balanced on their (15)  make the trek to the community well, and children donkeys haul the (16)  liquid in jerry cans.

All (17)  said, government sponsored building programs have also brought newer (18)  residences and utilities to some villages, particularly those outside (19)  Nile Valley in the Oases and the Red Sea (20)  areas.

16.（）