When considering the cost of roofing materials, many people take into account just the shingle prices. This is incorrect, as a roof made just of roofing shingles will not work. You also need to consider all the accessories that are included in a complete roof system.
The differences between emails and letters is that, emails are send electronically and arrives faster to the person that you are sending it too, while in the other hand letters takes a little bit longer to arrives to the person and can be lost from the mailing company especially whens sending it overseas also it cost money.
Well, first itâs important to remember that memos are usually meant for use only within the office and are sent through the internal mail system of the company. Anything that needs sending externally, to clients or suppliers etc, should be written in the more formal format of a letter. Secondly, they should be used when the information needs to be put in writing, not as a way to avoid speaking with people face-to-face. And lastly, they should be clear and brief.