$Q_x = 50,000 - 50P_x + 20P_j - 0.05M$ where $Q_x$ is the quantity demanded for yPad, $P_x$ be the price for yPad, $P_j$ be the average price of other similar products, and $M$ Q4 (10pt) Please interpret the coefficient (in front of $P_x$). Q5 (10pt) Please briefly discuss how you could obtain the coefficient.