<span>Every piece of evidence and every source must
be read or viewed skeptically and critically. and Each piece of evidence and source must be
cross-checked and compared with related sources
and pieces of evidence.</span>
WWI implemented trench warfare. Instead of everyone standing in a line people got down in trenches and fought each other. They would stay in these trenches for extended periods of time. The trenches were usually dirty and crowded.
Answer:
Protect itself from attack.
Explanation:
