能被植物光合作用吸收利用的太阳辐射称为______。
参考答案：生理辐射(或生理有效辐射)
The stranger stopped and turned around ___________to see is someone was following him.
A．every few meters
B．every a few meters
C．every other meters
D．every meters
为了做好沉降观测，水准点应尽量与观测点接近，其距离不应超过100m，应离开铁路、公路和地下管道至少5m，埋设深度至少在冻土线以下0.5m。
