It’s libby’s first day in college. when she approaches the professor to have an "add" form signed, she listens to other students to see if they address the professor as "professor," "dr.," "mrs.," or by her first name, and then she does the same. this is an example of

informational social influence

Explanation:

The term social influence is defined as the process when an individual's behavior is being influenced or directed due to imagined or real presence of other person.

Informational social influence: The term informational social influence refers to the process when an individual conforms with the other person to acquire knowledge and due to the fact that he or she thinks that the other person is right or other person's opinions is correct.

In the question above, the given statement is an example of informational social influence.

the correct answer is modern american cars are not available due to trade restrictions.

trade between cuba and the united states have serious restrictions. the u.s. imposed an economic embargo on cuba, that among other things means that modern american cars are not available due to trade restrictions.

in response to some governmental actions of the authorities from cuba, president john f. kennedy proclaimed an embargo on trade between both countries in february 1962. the trade embargo remains active until this day and was implemented directly by the departments of commerce and the department of treasury.

in president trump’s administration, there is a national security presidential memorandum that "strengthens the policy of the u. s.", affecting trade with cuba.

answer; biological;