Measures of Dis...

Consider the following statements:
(1) Mean is independent of change in scale and change in origin
(2) Variance is independent of change in scale but not in origin
Which of the above statements is/are correct?

The classes in which the lower limit or the upper limit is not specified are known as: _________.

Laspeyres Price Index =?

Laspeyres Price Index Number = ? 

Given the following set of data, what is the range 12 23 34 54 21 8 9 67:

Co-efficient of variation is?

The sum of squares of deviations for $$10$$ observations taken from mean $$50$$ is $$250 $$. Then Co-efficient of variation is

The mean deviation about the mean of the set of first $$n$$ natural numbers when $$n$$ is an odd number.

Find variance of the following data.

If the sum and sum of squares of $$10$$ observations are $$12$$ and $$18$$ resp., then, The $$S.D$$ of observations is :-