Which layer of the OSI model is responsible for error

For the price -quantity chart

The Pearson's correlation coefficient between following observation

A Poisson distribution has a double mode at x = 1 and x = 2. The probability for x = 1 or for x = 2 of these two values is:

For the study purpose, the mean of the observations is 148 gm and standard deviation is 17.4 gm. Approximately, the coefficient of variation equals to:

The mode of the given data set is 12. The sum of the frequency on both sides of mode are 16. The skewness:

The grouped data for the observations are

Class:                     1-3          3-5          5-7

If the multiple correlation coefficient of X1 on X2 and X3 is zero, then:

Marshall-Edgeworth Index number:

If r and R denote correlation and multiple correlation coefficient for the data set for X1, X2 and X3 . Which option is correct?