What are three types of business letters?

Of course there are more than 3 different categories of business letter but in the context of structure, there are three and they are:

Each is written in much the same manner, containing the same details, but the layout for each differs slightly.

Cheers!

it might be feelings and action sorry if i am wrong

from the political point of view it could be said that the candidate   is an effective speaker because she takes a strong position on the issue. it is an open discussion but probably she is making a presentation and can choose which subjects she wants to address. she is very likely to attain her aim which is to convince voters to accept her proposal.