Answer
(a) $NO$ being a product, the reaction shifts to the left side.
(b) $BrNO$ being a reactant, the reaction shifts to the right side.
(c) $Br_{2}$ being a product, the reaction shifts to the right side.
Work Step by Step
(a) According to Le Chatelier's Principle, when a product is added to an equilibrium mixture of a reaction,the equilibrium shifts to the left side (reactant) to decrease the amount/concentration of product.
(b) According to Le Chatelier's Principle, when a reactant is added to an equilibrium mixture of a reaction,the equilibrium shifts to the right side(product) to decrease the amount/concentration of reactant.
(c) According to Le Chatelier's Principle,when a product is removed from an equilibrium mixture of a reaction, the equilibrium shifts to the right side(product) to increase the amount/concentration of products.
