This is calculus 3 questions Please he

Problem 1 (20 points) a) Find the directional derivative of f (say, 2) = 3:2 + 'y2 + 22 at the point P(2, 1, 2) in the direction of E: = . 6332;, b) Find the differential of w(m,y, z, t) = . W \fProblem 5 (12 pts.): Set-up, but DO NOT Evaluate the following surface integral I = ff 3:3 (:15 where a is the portion of the cone 3: = V312 + 22 between the planes at = 1 and 93:4. Problem 9 (12 pts.): Use an appropriate form of the chain rule to find and aw av for: rs W = 12 + $2' r = uv, s =u - V