1. (2 points) Consider the production function f (r,x,) = (x? +x?) where a > 0 and 3 30. (a) Find the marginal product of input 1 and input 2. (1 point) (b) For which values of the parameters o and & does this production function exhibit increasing returns to scale (IRS), constant returns to scale (CRS), and decreasing returns to scale (DRS)? (1 point)