既能祛风湿,又能消骨鲠的药物是()
A.防己
B.防风
C.威灵仙
D.桑寄生
E.秦艽
参考答案:C
The building _______now beside the park was designed by a famous designer.
A.to be built
B.being built
C.built
D.building
如图所示,在一个光滑金属框架上垂直放置一根长l=0.4m的金属棒ab,其电阻r=0.1Ω.框架左端的电阻R=0.4Ω.垂直框面的匀强磁场的磁感强度B=0.1T.当用外力使棒ab以速度v=5m/s右移时,ab棒中产生的感应电动势E="____V," 通过ab棒的电流I="____A," ab棒两端的电势差Uab="____V," 在电阻R上消耗的功率PR____W, 在ab棒上消耗的发热功率PR=____,切割运动中产生的电功率P=____.