1. State the Chain Rule: a. z = f (x, y) is a differentiable function and x = s(t), y = p(t) - are functions of one variable, then: b. 2 = f (x,y) is a differentiable function, where x = q(s, f), y = p(s, r) - are functions of two variables, then: dz 2. Find the local maximum, minimum values and saddle point(s) of the function, if any. f(x,y) = 13' 2x 2y x2 _ 312