2. Omined Variable Biar Suppose that the true oil supply regression model from Part (1.) is gon/ = a + PouPon + Blaborlabor + ,, where gon, is the quantity of oil supplied (in trillion BTU), pon, is the price of oil (in $/ million BTU), and labor, is the annual wage (measured in $1,000). Instead of estimating the true model, you omit the variable labor,, leading to the following regression model: 9on = a + BouPoil + e;- Use the bias formula, Bias (Bon ) = Blabor cov(Pon labor) var (Paul) to answer the following questions. 1. If higher wages result in lower quantities of oil produced, do you expect the sign of labor to be positive or negative