For a normal distribution,which of the following relations holds true?

In a frequency distribution,if the mean and median are $21$ and $22$ respectively,then what is the approximate mode?

If $\alpha, \beta, \gamma$ are the mean deviations about the mean,median,and mode of the data $1, 2, 2, 3, 3, 3, 4, 6$ respectively,then

Determine which of the following statements is true: $(1)$ The mode can be calculated using a histogram. $(2)$ The median is not independent of the change of scale. $(3)$ Variance is independent of the change of origin and scale.

Find the mode of the following distribution:

Marks	$4$	$5$	$6$	$7$	$8$
No. of students	$6$	$7$	$10$	$8$	$3$

In a series,if $4$ appears $3$ times,$5$ appears $4$ times,$6$ appears $5$ times,$7$ appears $8$ times,$8$ appears $7$ times,and $9$ appears $6$ times,then the mode of the numbers is = .......