When speakers and listeners don’t share a common understanding of the major issues, it is difficult to communicate effectively. That is why it is important to do which of the following:

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Explanation:

One of the barriers to good and effective communication is when speakers and listeners do not share a common understanding of the major issues. Other barriers to effective communication includes the speaker talking too much, the speaker not being credible, the speaker is not focused on the particular topic and many more.

There are various reasons in which speakers and listeners don’t share a common understanding and in order to avoid this it is very important to do the following;

=> Research your Topic very well.

=> The speaker must stay audience centered. That is to say, the speaker must research and know many things about his or her Audience such as their belief in that subject, their age and their values.

In conclusion, the speaker has to understand his or her listeners by making sure that he or she has made enquiries about their cultural background, religion, opinion and many others

1) good with knives

2) good at manipulating

3) have lots of wisdom

explanation:

with the profits from the european sales, merchants purchased europe's manufactured  goods, including tools and weapons. then the merchants shipped those manufactured  goods, along with the  american  sugar and rum, to west africa where they were bartered for  slaves.