Answer:
Criminally negligent.
Explanation:
Negligence refers to the fact that you should have paid attention to details such as checking ID, calculating age, etc. but you didn't for one reason or another. This is a criminal act (apart from making an illegal sale) because it might lead to something more severe, like an accident or murder even, which might make you responsible for the crime.
Typing
Gender typing is the cognitive process where a child becomes aware of their own gender, including the expectations, roles, and stereotypes of that gender.
In this example, Stanford realizes his own gender is male, which is not associated with the color pink. He has been typed to believe that pink is not a masculine color. The toy aisle having mostly pink toys goes against this typing, causing confusion and distress from him, leading to his refusal to go near them.
The communist Manifesto was written by Karl Marx and by Friedrich Engels- Engels is the person you were looking for!
There is some discussion about the role of both authors in writing it, and some people suggest that Karl Marx did most of the work, with Engels having a smaller role.