QUESTION 7 Compute the following limit, or show that it doesn't exist. Make sure to justify your answer in full. I' - 2ry + y lim (x,y) + (0,0) QUESTION 8 Compute the following limit, or show that it doesn't exist. Make sure to justify your answer in full. lim y sin(x) QUESTION 9 Let f(x, y) = ex-ty (a). Find the domain of f. (b). Determine whether the values 0, 1, and -1 are in the range of f. Justify your answer. (c). Find and sketch the level curves f(x, y) = 1 and f(x, y) = _. You may draw all of them in the same plane. (d). Compute the following limit, or show that it doesn't exist. Justify your answer. lim f(x, y) (I,1) +(0,0) (e). (Optional; extra credit, 5 points.) Find the range of f. Justify your