Pet's facts or myths?

Have you ever had a pet? Do you have a pet now? Either way, which of the following statements are true?

1. Dogs are color blind

2. Cats always land on their feet

3. If a dog's nose is warm, it means it's sick

4. If a dog is wagging its tail, it is happy

5. A dog's mouth is cleaner than a human's mouth

6. One year of a dog's life is equal to 7 years of a human's life

7. You can't teach an old dog new tricks

8. Cats purr because they are happy

9. Cats can see in the dark

10. Dogs eat grass to throw up