Suppose that the demand and supply functions for good x are given as follows: $Q_x^d = 600 - 2P_x - I + P_y$ \\
and $Q_x^s = P_x - 2t + s - 2f$ where $P_x$ denotes the price of good x, $P_y$ denotes the price of a related product \\
y, I denotes income, t denotes tax firms face, s denotes subsidy and f denotes factor prices.\
What happens to the demand and supply of x as factor prices (f) falls?