Usually 12
5400
inches
19 inches is the average size of a regular backpack
Depends on the size of the books.
A typical school bag, or "backpack" will measure anywhere between 16 inches to 18 inches tall, 12 inches to 14 inches wide, and 4 inches to 5 inches deep.
Two
You would use cm if you were in Canada and inches if you were in USA.
A haversack is different from a backpack in many ways. For example, a haversack only has one strap to hold the bag on one's shoulder, while a backpack has two.
two
The average price of a household backpack vacuum is $250. Many things determine the price of a backpack vacuum including hepa rating and the number of attachments. Industrial backpack vacuums are much more expensive.
There are many retailers that offer backpack vacuums to customers such as online retailers and local stores. There are many different styles and sizes of backpack vacuums available and choosing one depends on a persons needs and personal preference.