Calculate the class interval of the required class.
 
Class
\(1\)
\(2\)
\(3\)
\(4\)
\(5\)
Interval
3.3 -  14.614.6 - 28.528.5 - 4040 - 43.743.7 - 54.7
 
The class interval of class \(5\) is .