在水稻→虫→青蛙这条食物链中,如果大量捕杀青蛙,最终造成的后果是[ ]
A.水稻减少
B.水稻增产
C.虫的数量减少
D.虫和水稻的数量均会减少
答案:A
What ______ at seven yesterday morning?
A.is she doing
B.was she doing
C.did she do
D.does she do
某同学用一只装有2 g水银的温度计,测量烧杯中水的温度,若温度计示数上升了50℃,则温度计内的水银吸收了多少热量?