Hello, I need a little explanation on how to answer this question:The acetylamido group is moderately

Hello, I need a little explanation on how to answer this question:

The acetylamido group is moderately

activating group in electrophilic aromatic substitution reactions. What does this mean? in this reaction, only the orthodox and para isomers are produced. based on the mechanism explain these observations (acetylamido group is activating and only orthodox and para isomers are formed)?

Thank you very very much!