19) F - x2i + y2j: the curve C is the closed counterclockwise path around the triangle with vertices at 19) (0, 0), (2, 0), and (0, 5) A) - 10 B) 70 c) 10 D) 0 9 Find the mass of the wire that lies along the curve r and has density &. 20) r(1) - /15, 23 12 - 8 1 + 71j. Ost =1; 6 - 31 20) A) 169 15 units B) 10 units C) 57 units D) $ unitsProblems 21-22: Test the vector field F to determine if it is conservative. 21) F = xyi + yj + zk 21) A) Conservative B) Not conservative 22) F = - cos x cos yi + sin x sin yj - sec2 zk 22) A) Not conservative B) Conservative 10 Problems 23-25: Find the potential function f for the field F. 23) F = 9xBy3z9i + 3x9y2z"j + 9x"y328k 23) A) f(x, y. z) = x27y9227 + c B) f(x, y. z) _ xy y329 243 C) f(x, y. z) = x" y3z" + c D) f(x, y. z) = xy3z" + 3x9y2z" + 9x" y328 + c