【单选题】设线数 的光栅其零级主极大强度为 ,在其他条件相同时, 的光栅其零级主极大强度为 ,则 为( )
【单选题】Why is Margaret Chan disappointed?
A.
No important steps to stop climate change have been taken.
B.
Many droughts and floods have been reported worldwide.
C.
No deal on climate change was struck at the Copenhagen conference.
【单选题】我国利用微生物发酵酿酒的考古证据可追溯到什么时间?
【单选题】设线数N1=600的光栅其零级主极大强度为I1,在其他条件相同时,N2=1800的光栅其零级主极大强度为I2,则I2/I1为
【单选题】The research by Hardisty and Weber aims at ______.
A.
changing people's view on climate change
B.
altering people's concept on consumption
C.
seeking ways to convince people to limit climate change
D.
increasing the benefit from acting on climate change