Because she has learned the importance of the tea ceremonies once her mother explained
No, it is not imagery.
Imagery would tell you how he looks specifically, these are all general observations. You cannot imagine him in a detailed manner with this info. Is he blond? Is he a brunette? Does he have pale skin? If we can't make an image in our mind, then it's not imagery. Imagery consists of SPECIFIC details. For example, imagery would be, "His eyes were a crystal blue, as if they were made of water. It seemed like you could jump right into them and swim for hours."
The tone is important in all writing it conveys the authors attitude towards the topic.
It shows that King is optimistic in the face of a very large task.
