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a)

Cunsider the function z, Ex} 2 :1 + 2: + y: z 49' + z: + 14. The level surface f{z,y,z} = 4, is the sphere Select one: D a. at radius 4 with the center at {1, 2,3] D b. of radius 2 with the center at {1, l,3-] D c. of radius 2 with the center at {2, l,4] D d. of radius 4 with the center at {2, l,3-] D e. of radius 2 with the center at {1,2,3-] \fThe tangent line to the curve C of the intersection of the surface z = f(I, y) = I,/I + yand the plane y = 3 at the point P(1, 3, 2) has the slope O a. 2/3 O b. 1/2 O c. 1/4 O d. 9/4 Oe. 2