Given x y z 4 and Po(1,2,1), find the following (a) Find the equation for the tangent plane at the point Po on the given surface. (b) Find the equations for the normal line at the point Po on the given surface. (a) Find the equation for the tangent plane at the point Po on the given surface 0-0 (b) Find the equations for the normal line at the point Po on the given surface. Let x=1+1 x= y= 2tho (Type expressions using t as the variable.)