Please advise, need your help, thanks!

Consider a production function of multiple inputs. Choose all the correct statements below: O For a production function to have positive but declining marginal product of an input, the first and second derivatives of the production function with respect to that input should be, respectively, positive and negative O If the marginal product of an input is constant, the second partial derivative of the production function with respect to that input is positive O For a production function to have positive but declining marginal product of an input, the first and second derivatives of the production function with respect to that input should both be positive For a production function to have positive but declining marginal product of an input, the first and second derivatives of the production function with respect to that input should both be negative O If the marginal product of an input is constant, the second partial derivative of the production function with respect to that input is negative O For a production function to have positive but declining marginal product of an input, the first and second derivatives of the production function with respect to that input should be, respectively, negative and positive