可以使用 、相似系数、相关系数等指标，来衡量不同地物之间的光谱相似性。

ies conducted during the 1970s on prents-children reltionship indicted tht ______.dolescence did not cuses much troubles clinicinsnd theorists hd stted B．children’sggressivenessnd rebelliousness were growing C．children-prents reltionship ws declining D．teengers becme even morebhorrent of their prentsA．adolescence did not cause as much trouble as clinicians and theorists had statedB．children’s aggressiveness and rebelliousness were growingC．children-parents relationship was decliningD．teenagers became even more abhorrent of their parents

A、20MW
B、12MW
C、10MW
D、15MW

材料请回答 16～22 Smoking Since 1939, numerous studies have been conducted to determine whether smoking is a health hazard.The trend of the evidence has been consistent and indicates that there is a serious health risk.Research teams have conducted studies that show beyond all reasona-ble doubt that tobacco smoking is associated with a shortened life expectancy （）And low tar tobacco are claimed to make smoking to some extent sa-fer, but they can only slightly reduce,not eliminate,the hazards． 第 16 题 It is easy to determine whether smoking is hazardous． A．RightB．WrongC．Not mentioned