Please check the correctness?

1. If they go to Washington, they will see the White House. 2. If mum gave her a sweet, she would stop crying. 3. If he arrives later, he will take a taxi. 4. We would understand him if he spoke slowly. 5. Andy will cook dinner if we buy the food. 6. I will prepare breakfast if I woke up early. 7. If you hate walking in the mountains, you will not enjoy the tour. 8. Janet would go jogging if she did not have to do her homework.