The correct answer is: Only 1.
A cartel is an informal agreement among the firms to avoid competition. This can be done by setting prices, dividing up the market, or coordinating production. Cartels are illegal in many countries, but they can be difficult to detect and enforce.
There is no free entry of firms in a monopoly market. A monopoly is a market structure in which there is only one seller of a good or service. The monopolist has a great deal of market power and can charge a high price for its product.
There is no full control over price in perfect competition. Perfect competition is a market structure in which there are many sellers of a good or service, the goods or services are identical, there is free entry and exit into the market, and buyers and sellers are well-informed. In a perfectly competitive market, firms have no control over price. The price is determined by the market forces of supply and demand.
Statement 1 is correct because a cartel is an informal agreement among the firms to avoid competition. Statement 2 is incorrect because there is no free entry of firms in a monopoly market. Statement 3 is incorrect because there is no full control over price in perfect competition.