I need to know if these statements are true or false. I don't need an explanation.

1)An import tariff of a small country under perfect competition has no effect on terms of trade.

2)Free trade may reduce the market power of a monopoly relative to autarky

3)Under perfect competition, export subsidies always result in a terms-of-trade loss.

4)A large country may benefit from import tariff under perfect competition because the tariff affects the terms of trade.

5)Agricultural subsidies of the developed countries benefit such developing countries which import agricultural products

6)With imperfect competition, it is possible that a small country benefits from import tariff

7)In case of infant industries government intervention by import tariffs is always justified.

8)Prisoner's dilemma is a game theoretic situation where the equilibrium of a game is such that it maximizes the sum of both players' payoffs but the welfare of the rest of the world is not optimal.

9)Regional trade agreements may lead to either welfare losses or welfare gains to the member countries.