her is this from google
"A system of temporary reference points established in the field allows users to move freely within the study area without losing the geo-referencing. It allows the user to perform the mapping of trees, deadwood, transects, repeated measurements and data verification."
A triangle’s angles are equivalent to 180 degrees so the third angle would have to equal 20 degrees
It is absolutely true that China is seeking to lessen its dependence on coal by developing more hydro power resources. The correct option among all the options given in the question is the first option. China is blessed with natural rivers and it is slowly trying to reduce its dependence on coal powered plants to hydro power plants. This is also a great step towards reducing air pollution.