【单选题】Plant Gas Scientists have been studying natural sources of methane for decarlesd but hadn’t regarded plants as a produeer,notes Frank Keppler,a geochemist at the Max Planck Institute for Nuelear Physi...
A.
It was produced from plants.
B.
It was not a greenhouse gas.
C.
It was pmduced in OXygen-free environments.
D.
It traps more heat than any other greenhouse gas.
【单选题】在黑暗处呆的较长时间后注视灯光,再回到暗处。这时在人脑中留有灯的亮点。这种感觉现象是( )。
【单选题】在黑暗处呆的较长时间后注视灯光,再回到暗处。这时在人脑中留有灯的亮点。这种感觉现象是( )
【单选题】金刚烷胺治疗震颤麻痹的作用机制主要是()