Final answer:
The White House plumbers and the "dirty tricks" squad were involved in operations such as the Watergate break-in, and sabotaging political opponents' campaigns through various unethical and illegal means.
Step-by-step explanation:
The White House plumbers and the "dirty tricks" squad were involved in various unethical and illegal activities during the Nixon administration. One of their primary operations was the break-in at the Democratic National Committee headquarters at the Watergate office complex, which was an attempt to gather intelligence on political opponents. They also engaged in the sabotage of political adversaries' campaigns by means such as forging documents, disseminating false information, and other forms of political espionage.