Answer:
The two firms will manipulate the market in unison, to maintain the same price, which guarantees the optimum benefit for both firms, as opposed to if one or both of them reduces its price.
Step-by-step explanation:
A cartel is a group of independent market participants that collude with each other in order to improve their profits and dominate the market. Cartels are usually in the same line of business, and they form a type of alliance as competitors. Cartel use price fixing, bid rigging, and reductions in output, to dominate the market and to maximize their profit. They are usually frowned upon in a free market system.
In this case, if the the two firms Boeing and Rolls-Royce operates as a cartel, they will bend the market rules by fixing their prices, instead of letting market drivers like demand and supply to determine their selling price, they might also reduce their output so that they both have the same level of output, or do any other form of manipulation in unison to maintain the same price. This is because both companies will benefit equally if they maintain the same price, as opposed to if one or both of them reduces price.