Descriptive Sta...

If the standard deviation for the marks obtained by a student in monthly tests is 36 then the variance is

Which one of the following statements is correct?

On joining the points if we get a straight line, that graph is called.

Five chemical factories $$P,\,Q,\,R,\,S\;and\;T$$ are located in different cities along a river bank. Municipal officer, in order to estimate the pollution caused by these factories, counted the number of fishes present at the places where these factories discharged their wastes into the river. A graph as shown here, is plotted based on the observations.
What can be inferred from the graph ?

To compare the relative growth or decline of two or more series the most appropriate chart to be drawn would be 

In a bar chart:

The difference in the sales of apple products for the year $$2000$$ and $$2001$$ is?

The sum of sales of apple products in the years $$1999$$ and $$2000$$ is approximately equal to that in?

The percentage increases in sales from $$2000$$ to $$2003$$ was?

What is the ratio between total sales rate of apple product in the year $$2001 $$ to $$2003$$?