What frequency is indicated by the tally marks $?$

True lower limit of class $26 - 30$, when the classes are $26 - 30, 31 - 35, 36 - 40 ....$,  is _____.

Observe the following table $:$

Then, the value of $k=$_____.

The class mark of the class $10.5-20.5$ is_____

Lower limit of class $25-30$ is _____.

Who is my friend?

I’ve a friend with me always,

In the nights and through the days.

When I run he runs with me,

Sometimes I lead, sometimes he.

When it’s dark he can’t be seen,

Do you know which friend I mean?

Read the poem carefully and answer the below question.

The letter used more often _____

        If the class-marks of a distribution are $22, 27, 32$, then the width of each class is_____

       The range of the data $12, 17, 9, 4, 18, 17, 27, 8$; is _____.