The average amount of rainfall throughout the summer months for northeast part of united states is 11.52 inches. A researcher chooses a random sample of 10 cities in northeast and finds out that the average amount of rainfall for 1995 was 7.42 inches. The standard deviation of sample is 1.3 inches. Supposes that the population is approximately normally distributed. At a=0.05, can it be concluded that for 1995 the mean rainfall was below 11.52 inches?