B. Add the main points below under the correct topic sentence. 1. The cost of airplane tickets gets higher every year. 2. Travelers are on international flights for long periods of time. 3. More and more airlines require passengers to pay an extra fee to check their luggage. 4. Seats are generally small and close together. 5. Many airlines no longer serve free meals, so passengers must pay for food. 6. Time zone changes cause problems. Topic Sentence: Air travel is becoming increasingly expensive. Main Points: ____ Topic Sentence: International air travel is often uncomfortable. Main Points: ____