The variance is
1. directly proportional to the average squared difference between all pairs of observations.
2. smallest when calculated from the mean.
3. denoted by symbol cr.
4. described as the dispersion of the distribution.
Which of the statements given above is/are correct?

A. extending technical knowledge to wives or ladies in urban and rural areas B. extending knowledge about agricultural machinery C. extending knowledge on the managing and running of industries D. All of the above

A. need oriented B. local resource based C. problem solution oriented system D. All of the above

A. agricultural extension B. home science extension C. agricultural engineering extension D. All of the above

A. O. P. Dahama B. Mildred Horton C. J. P. Leagans D. Kelsey and Hearne