The correct plural form of echo is echos or echoes. Either way it is grammarly correct. I believe that echoes is the correct form.
echoes
Answer:
yea so just argue if you are for or against it...
and then find evidence to back ur claims up
Answer:
Revived Catholicism
Explanation:
The major achievement of Francis de sales, was Revived Catholicism.
In this instance, you would use <em>in </em>university. <em>At </em>is only used before specific terms such as "I am studying <em>at </em>Harvard" or "I am studying <em>at </em>Williams College."
For the second question, context must be applied. If you are talking about the corner of a room, <em>in </em>should be used. However, if you are talking about the corner of a sidewalk or street, <em>on </em>or <em>at </em>would be correct.
I hope I helped!