completely show the solutions for the problems

a] Let h {15, v, z] = 21:33; + Says - 1'23, wherein the directional derivative ofo: at {1, 1, 1] along = {2, -2, -1} is 1. If rt is a fixed constant, then solve for its value. bl Set up an iterated double integral equal using rectangular coordinates to the volume of the solid in the 15' octant that is bounded from above lav the parabolic cvlinder : = 4 - 3r: , bounded from hElW lav the xv-plane, and bounded from the sides by a} vz-plane, h] plane v=x, and c] parabolic cvlinder FI'IE- Show the sketch of the graph