起重机的钢绳将500N的物体匀速提高6m后,又水平匀速移动4m,钢绳对物体所做的功为( )
A:5000J
B:3000J
C:2000J
D:1000J
Which of the following doesn't have a linking sound (连读)?
雅鲁藏布江大峡谷科考测量采用的地理信息技术是( )。