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A hurricane policy covers both water damage, X, and wind damage, Y, where X and Y have joint density function 0.13e-0.50-0.29 - 0.06e--0.2y - 0.06e-0.5:-0.4y + 0.12e-r-0.4y f (I, y) = r >0,y>0 otherwise Calculate the expected value of X3