Answer:
Non response error
Explanation:
Non response error - it is refer to that error of sampling when samples are not taken into consideration. In this case samples do not replied either they are not ready reply or do not want to reply.
In the given question also 1000 sample units is taken into consideration but only 1 % has respond which show that sample do not respond to the survey.
Deforestation but mainly Desertification.
They avoid being detected because this would throw off the behavior patterns that exist naturally and they don't want their presence being known since this might throw it off.<span />
Answer:
They might have been written down and codified because they wanted to keep it more of a secret but idk i hope this helps
Explanation: