SPOT THE ERROR - DOHA 5

Found at Doha Zoo

Sentence in line (1):

The word "adviced" is wrongly spelled
"Their safety is their own responsibility" would mean the children are responsible for their own safety so this should be good news for the parents.

Sentence in line (4):

"It's not allowed.." is wrong. Perhaps, it should be written: "Visitors are not allowed to bring in..."

Sentences in line (2) and (4):

They sound more like the authority is begging rather than giving instructions.

Compare these two expressions, with and without the comma:

"Please, leave some of the food for me"
and
"Please leave some of the food for me".