菱形ABCD的一条对角线长为6，边AB的长是方程x2-7x+12=0的一个根，则

The effect of the baby boom on the schools helped to make possible a shift in thinking about the role of public education in the 1920’s. In the 1920’s, but especially (1) the Depression of the 1930’s, the United States experienced a (2) birth rate. Then with the prosperity (3) on by the Second World War and the economic boom that followed it, young people married and (4) households earlier and began to (5) larger families than had their (6) during the Depression. Birth rates rose to 102 per thousand in 1946, 106.2 in 1950, and 118 in 1955. (7) economics was probably the most important (8) , it is not the only explanation for the baby boom. The increased value placed (9) the idea of the family also helps to (10) this rise in birth rates. The baby boomers began streaming (11) the first grade by the mid-1940’s and became a (12) by 1950. The public school system suddenly found itself (13) The wartime economy meant that few new schools were buih between 1940 and 1945. (14) , large numbers of teachers left their profession during that period for better-paying jobs elsewhere.

(15) , in the 1950’s, the baby boom hit an antiquated and inadequate school system. Consequently, the custodial rhetoric of the 1930’s no longer made (16) ; keeping youths ages sixteen and older out of the labor market by keeping them in school could no longer be a high (17) for an institution unable to find space and staff to teach younger children. With the baby boom, the focus of educators (18) turned toward the lower grades and back to basic academic skills and (19) . The system no longer had much (20) in offering nontraditional, new, and extra services to older youths.

15().

A. Nevertheless

B. Therefore

C. Furthermore

D. Hence fore

脓胸纤维板剥除术的适应证（）

A.病程短的慢性脓胸，肺内无病变

B.急性包裹性脓胸

C.肺内有病灶，肺不能复张

D.伴支气管胸膜瘘

E.病程久，肺有纤维变性

近因判定的正确与否，关系到保险责任的归属问题，下列关于近因的认定与保险责任的确定的说法中，错误的是（）。

A.单一原因致损，且该原因属于被保风险，则保险人负赔偿责任

B.如为多种原因致损，且多种原因均属被保风险，则保险人负赔偿责任

C.连续发生的多项原因致损，若前因属于被保风险，但后因属于除外责任的，保险人不负赔偿责任

D.在一连串连续发生的原因中，有一项新的独立的原因介入，导致损失，若新的独立的原因为被保风险，则保险人承担保险责任

患者，女，45岁，高空坠落所致“复合性损伤”，入院神志清楚，清创缝合术后第三天出现昏迷，呼出气有“烂苹果”味。

为确诊需做下列哪项检查（）。

A.血气分析、血电解质

B.血糖、酮体、尿糖

C.心脏彩超、心电图

D.血尿常规

E.脑部CT、心电图

雇主责任保险合同的受益人是( )。

A．与雇员有雇佣关系的雇主
B．与雇主有雇佣关系的雇员
C．与保险人有保险关系的雇主
D．与保险人有保险关系的被保险人