The quote states that we should be using solar energy before our limited amount of naturally occurring oil and coal runs out. Meaning; we should be proactively working towards solar power rather than to wait for our resource to run out to start.
Answer:
The Mexico–United States barrier (Spanish: barrera México–Estados Unidos), also known as the border wall, is a series of vertical barriers along the Mexico–United States border intended to reduce illegal immigration to the United States from Mexico.
Explanation:
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."
