Evaluate R y sin(xy) dA, where R = [3, 9] × [0, π]. SOLUTION 1 If we first integrate with respect to x, we get R y sin(xy) dA = π 0 9 3 y sin(xy) dx dy = π 0 x = 9 x = 3 dy = π 0 dy = π 0 = .

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables