PPSC Past Paper Deputy Accountant Finance Department-2019 Evening, General Knowledge MCQs, PPSC Solved Past Papers MCQsWhen no tariffs are imposed on all imports and exports, it is called?A. Preferential Trade B. Free Trade C. Balance of Trade D. Non-Tariff Barriers Christopher Columbus who accidently discovered America was citizen of?Choose the meaning of idiom: “To break a lance with”.