Which of these represent qualitative data________?

Three brands of coffee are rated for tasted on a scale of 1 to 10. Six persons are asked to rate each brand so that there is a total of 18 observations.The appropriate test to tasted equally good is________?

Non-sample errors are reduced by:________?

Mean deviation of Normal Distribution is________?

The average of first n natural numbers is________?

For distribution Function F(X),F(-∞)=0 and F(∞)=?