Karachi was a part of Alexander the Great's success?
Rationale first then the answer.
Karachi is a city in modern day Pakistan. Krokola was an ancient port located in what is now Karachi. Alexander the Great stationed his fleet in Krokola on his way to Babylon. Alexander the Great defeated Darius and conquered Babylon before expanding his empire.. The answer is: yes.

Are Mayors safe from harm from the federal government?
Rationale first then the answer.
The Mayor of Portland is Ted Wheeler. Ted Wheeler was tear-gassed by federal troops sent to his state.. The answer is: no.

Can methane be seen by the naked eye?
Rationale first then the answer.
Methane is a gas. Methane is colorless. Methane is odorless.. The answer is: no.