10. [10] Annual rainfall is measured at numerous weather stations throughout Pennsylvania. The average (mean) rainfall is 40 inches with standard deviation 10 inches. Assume that the rainfall is normally distributed among the stations.

(i) Sketch a graph of the pdf corresponding to the rainfall distribution.

(ii) Indicate as an area on your sketch in (i) the probability of 35 inches or less of rainfall measured.

(iii) Use an online normal distribution calculator to give the probability of measuring 35 inches or less.