Can you do these 3 problems please Thank you!

For the function f(x, y) = - 3e" sin(y), find a unit tangent vector to the level curve at the point ( - 4, -2) that has a positive a component. Present your answer with three decimal places of accuracy. Note: y is in radians.Find an equation for the tangent plane to the surface a | 3 = 31:6 (305(3) at the point (3,1,0). Enter your answer as an equation Example: y=3x"2+l, 2+x+y=3 Be sure your variables match these in the quesern Calculate Dof( - 3, -1, -5) in the direction of d = -37 -23 - E for the function f(x, y, z) = 3x' - my - 4y' - 5x + 2yz + 226 - TZ. Round your answer to 3 decimal places. TIP Enter your answer as an integer or decimal number. Examples: 3, -4, 5.5172 Enter DNE for Does Not Exist, oo for Infinity