What do you think about data set if standard deviation to be zero?

Step-by-step explanation:

all elements of the data set have the same value. therefore there is no difference of the individual values to the mean value.

and the sum of these differences is therefore also 0.

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents